Canada FluWatch Weekly Reports 2012-2013 Season Weeks 33 & 34

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August 26 to September 8, 2012 (Weeks 35 & 36)

Posted 2012-09-14For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w36_12/pdf/fw2012-36-eng.pdf">2011-2012 FluWatch: August 26 to September 8, 2012 (Weeks 35 & 36) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 6 pages)

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Overall Influenza Summary

• Influenza activity in Canada remains low; however several regions have reported either sporadic or localized activity over the two-week period (in BC, MB, ON & QC)
• In weeks 35 and 36, a total of 17 laboratory detections of influenza were reported of which 82.4% were for influenza A viruses (7 A(H3) and 7 A(un-subtyped)) and 17.6% for influenza B viruses
• One region (in MB) reported localized activity in week 36 due to an outbreak in a long-term care facility
• No influenza-associated hospitalizations were reported over the two-week period
• The ILI consultation rate in weeks 35 and 36 were within the expected levels for this time of year

<HR>NOTE: This is the first surveillance report for the 2012-2013 influenza season.Bi-weekly reports will continue until October 12, 2012. However, laboratory detections reported through the RVDSS and influenza activity level maps will be updated weekly on the FluWatch website.

Influenza Activity (geographic spread) and Outbreaks

In week 35, 2 regions (within BC & ON) reported sporadic activity while the rest reported no activity. In week 36, 1 region (within MB) reported localized activity, 2 regions (within ON & QC) reported sporadic activity and the rest reported no activity (see Figure 1). Note that no data was received from AB, SK, NS, PEI and YT for week 35 and no data was received from SK, PEI, NL and YT for week 36. One new outbreak was reported in week 36 in a long-term care facility (Figure 3) in MB and was due to influenza A/H3.
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 36





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N=56)


† sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The proportion of positive influenza tests increased slightly from two weeks ago (when the percent positive was 0.2%) and was 0.9% in week 35 and 0.6% in week 36 (Figure 4 & 5). The proportion of positive detections for influenza A (0.8% in week 35 and 0.4% in week 36) was slightly higher than the proportion positive for influenza B detections (0.1% and 0.2% respectively). Over the two week period, influenza A detections were reported in BC, AB, MB, ON, QC & NL while influenza B detections were reported in AB, SK & QC.
Cumulative to date of influenza virus detections by type/subtype is as follows: 82.4% influenza A (50.0% - A(H3) and 50.0% - unsubtyped) and 17.6% influenza B (Table 1).
Detailed information on age and type/subtype of the positive influenza cases to date will be presented once more information becomes available (Table 2).
The percentage positive for rhinovirus detections was similar to previous weeks (18.0% & 23.1% in weeks 35 & 36 respectively) and remains the highest compared to the other respiratory viruses. The percentage positive for parainfluenza viruses continued to decline and was 1.7% in week 36. The percentage positive for the other respiratory viruses in week 36 remained low: RSV-.7%; adenovirus-1.1%; hMPV-0.8%; and coronavirus-0.7% (Figure 5). For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(August 26 to September 8, 2012)
</TH><TH id=ac9 colSpan=6>Cumulative
(August 28, 2012 to September 8, 2012)
</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B
</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B
</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*
</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*
</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no test for subtyping was performed. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals.</TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignCenter headers="ar1 ar2 ac1 ac2 ac3">2</TD><TD class=alignCenter headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD class=alignCenter headers="ar1 ar2 ac1 ac2 ac5">1</TD><TD class=alignCenter headers="ar1 ar2 ac1 ac2 ac6">0</TD><TD class=alignCenter headers="ar1 ar2 ac1 ac2 ac7">1</TD><TD class=alignCenter headers="ar1 ar2 ac1 ac8">0</TD><TD class=alignCenter headers="ar1 ar2 ac9 ac10 ac11">2</TD><TD class=alignCenter headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD class=alignCenter headers="ar1 ar2 ac9 ac10 ac13">1</TD><TD class=alignCenter headers="ar1 ar2 ac9 ac10 ac14">0</TD><TD class=alignCenter headers="ar1 ar2 ac9 ac10 ac15">1</TD><TD class=alignCenter headers="ar1 ar2 ac9 ac16">0</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignCenter headers="ar1 ar3 ac1 ac2 ac3">2</TD><TD class=alignCenter headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD class=alignCenter headers="ar1 ar3 ac1 ac2 ac5">1</TD><TD class=alignCenter headers="ar1 ar3 ac1 ac2 ac6">0</TD><TD class=alignCenter headers="ar1 ar3 ac1 ac2 ac7">1</TD><TD class=alignCenter headers="ar1 ar3 ac1 ac8">1</TD><TD class=alignCenter headers="ar1 ar3 ac9 ac10 ac11">2</TD><TD class=alignCenter headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD class=alignCenter headers="ar1 ar3 ac9 ac10 ac13">1</TD><TD class=alignCenter headers="ar1 ar3 ac9 ac10 ac14">0</TD><TD class=alignCenter headers="ar1 ar3 ac9 ac10 ac15">1</TD><TD class=alignCenter headers="ar1 ar3 ac9 ac16">1</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignCenter headers="ar1 ar4 ac1 ac2 ac3">0</TD><TD class=alignCenter headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD class=alignCenter headers="ar1 ar4 ac1 ac2 ac5">0</TD><TD class=alignCenter headers="ar1 ar4 ac1 ac2 ac6">0</TD><TD class=alignCenter headers="ar1 ar4 ac1 ac2 ac7">0</TD><TD class=alignCenter headers="ar1 ar4 ac1 ac8">1</TD><TD class=alignCenter headers="ar1 ar4 ac9 ac10 ac11">0</TD><TD class=alignCenter headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD class=alignCenter headers="ar1 ar4 ac9 ac10 ac13">0</TD><TD class=alignCenter headers="ar1 ar4 ac9 ac10 ac14">0</TD><TD class=alignCenter headers="ar1 ar4 ac9 ac10 ac15">0</TD><TD class=alignCenter headers="ar1 ar4 ac9 ac16">1</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignCenter headers="ar1 ar5 ac1 ac2 ac3">3</TD><TD class=alignCenter headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD class=alignCenter headers="ar1 ar5 ac1 ac2 ac5">3</TD><TD class=alignCenter headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD class=alignCenter headers="ar1 ar5 ac1 ac2 ac7">0</TD><TD class=alignCenter headers="ar1 ar5 ac1 ac8">0</TD><TD class=alignCenter headers="ar1 ar5 ac9 ac10 ac11">3</TD><TD class=alignCenter headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD class=alignCenter headers="ar1 ar5 ac9 ac10 ac13">3</TD><TD class=alignCenter headers="ar1 ar5 ac9 ac10 ac14">0</TD><TD class=alignCenter headers="ar1 ar5 ac9 ac10 ac15">0</TD><TD class=alignCenter headers="ar1 ar5 ac9 ac16">0</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignCenter headers="ar1 ar6 ac1 ac2 ac3">5</TD><TD class=alignCenter headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD class=alignCenter headers="ar1 ar6 ac1 ac2 ac5">2</TD><TD class=alignCenter headers="ar1 ar6 ac1 ac2 ac6">0</TD><TD class=alignCenter headers="ar1 ar6 ac1 ac2 ac7">3</TD><TD class=alignCenter headers="ar1 ar6 ac1 ac8">0</TD><TD class=alignCenter headers="ar1 ar6 ac9 ac10 ac11">5</TD><TD class=alignCenter headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD class=alignCenter headers="ar1 ar6 ac9 ac10 ac13">2</TD><TD class=alignCenter headers="ar1 ar6 ac9 ac10 ac14">0</TD><TD class=alignCenter headers="ar1 ar6 ac9 ac10 ac15">3</TD><TD class=alignCenter headers="ar1 ar6 ac9 ac16">0</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>

</TH><TD class=alignCenter headers="ar1 ar7 ac1 ac2 ac3">1</TD><TD class=alignCenter headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD class=alignCenter headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD class=alignCenter headers="ar1 ar7 ac1 ac2 ac6">0</TD><TD class=alignCenter headers="ar1 ar7 ac1 ac2 ac7">1</TD><TD class=alignCenter headers="ar1 ar7 ac1 ac8">1</TD><TD class=alignCenter headers="ar1 ar7 ac9 ac10 ac11">1</TD><TD class=alignCenter headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD class=alignCenter headers="ar1 ar7 ac9 ac10 ac13">0</TD><TD class=alignCenter headers="ar1 ar7 ac9 ac10 ac14">0</TD><TD class=alignCenter headers="ar1 ar7 ac9 ac10 ac15">1</TD><TD class=alignCenter headers="ar1 ar7 ac9 ac16">1</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>

</TH><TD class=alignCenter headers="ar1 ar8 ac1 ac2 ac3">0</TD><TD class=alignCenter headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD class=alignCenter headers="ar1 ar8 ac1 ac2 ac5">0</TD><TD class=alignCenter headers="ar1 ar8 ac1 ac2 ac6">0</TD><TD class=alignCenter headers="ar1 ar8 ac1 ac2 ac7">0</TD><TD class=alignCenter headers="ar1 ar8 ac1 ac8">0</TD><TD class=alignCenter headers="ar1 ar8 ac9 ac10 ac11">0</TD><TD class=alignCenter headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD class=alignCenter headers="ar1 ar8 ac9 ac10 ac13">0</TD><TD class=alignCenter headers="ar1 ar8 ac9 ac10 ac14">0</TD><TD class=alignCenter headers="ar1 ar8 ac9 ac10 ac15">0</TD><TD class=alignCenter headers="ar1 ar8 ac9 ac16">0</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>

</TH><TD class=alignCenter headers="ar1 ar9 ac1 ac2 ac3">0</TD><TD class=alignCenter headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD class=alignCenter headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD class=alignCenter headers="ar1 ar9 ac1 ac2 ac6">0</TD><TD class=alignCenter headers="ar1 ar9 ac1 ac2 ac7">0</TD><TD class=alignCenter headers="ar1 ar9 ac1 ac8">0</TD><TD class=alignCenter headers="ar1 ar9 ac9 ac10 ac11">0</TD><TD class=alignCenter headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD class=alignCenter headers="ar1 ar9 ac9 ac10 ac13">0</TD><TD class=alignCenter headers="ar1 ar9 ac9 ac10 ac14">0</TD><TD class=alignCenter headers="ar1 ar9 ac9 ac10 ac15">0</TD><TD class=alignCenter headers="ar1 ar9 ac9 ac16">0</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>

</TH><TD class=alignCenter headers="ar1 ar10 ac1 ac2 ac3">0</TD><TD class=alignCenter headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD class=alignCenter headers="ar1 ar10 ac1 ac2 ac5">0</TD><TD class=alignCenter headers="ar1 ar10 ac1 ac2 ac6">0</TD><TD class=alignCenter headers="ar1 ar10 ac1 ac2 ac7">0</TD><TD class=alignCenter headers="ar1 ar10 ac1 ac8">0</TD><TD class=alignCenter headers="ar1 ar10 ac9 ac10 ac11">0</TD><TD class=alignCenter headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD class=alignCenter headers="ar1 ar10 ac9 ac10 ac13">0</TD><TD class=alignCenter headers="ar1 ar10 ac9 ac10 ac14">0</TD><TD class=alignCenter headers="ar1 ar10 ac9 ac10 ac15">0</TD><TD class=alignCenter headers="ar1 ar10 ac9 ac16">0</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>

</TH><TD class=alignCenter headers="ar1 ar11 ac1 ac2 ac3">1</TD><TD class=alignCenter headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD class=alignCenter headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD class=alignCenter headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD class=alignCenter headers="ar1 ar11 ac1 ac2 ac7">1</TD><TD class=alignCenter headers="ar1 ar11 ac1 ac8">0</TD><TD class=alignCenter headers="ar1 ar11 ac9 ac10 ac11">1</TD><TD class=alignCenter headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD class=alignCenter headers="ar1 ar11 ac9 ac10 ac13">0</TD><TD class=alignCenter headers="ar1 ar11 ac9 ac10 ac14">0</TD><TD class=alignCenter headers="ar1 ar11 ac9 ac10 ac15">1</TD><TD class=alignCenter headers="ar1 ar11 ac9 ac16">0</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignCenter headers="ar1 ar12 ac1 ac2 ac3">14</TD><TD class=alignCenter headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD class=alignCenter headers="ar1 ar12 ac1 ac2 ac5">7</TD><TD class=alignCenter headers="ar1 ar12 ac1 ac2 ac6">0</TD><TD class=alignCenter headers="ar1 ar12 ac1 ac2 ac7">7</TD><TD class=alignCenter headers="ar1 ar12 ac1 ac8">3</TD><TD class=alignCenter headers="ar1 ar12 ac9 ac10 ac11">14</TD><TD class=alignCenter headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD class=alignCenter headers="ar1 ar12 ac9 ac10 ac13">7</TD><TD class=alignCenter headers="ar1 ar12 ac9 ac10 ac14">0</TD><TD class=alignCenter headers="ar1 ar12 ac9 ac10 ac15">7</TD><TD class=alignCenter headers="ar1 ar12 ac9 ac16">3</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(August 26 to September 8, 2012)
</TH><TH id=bc8 colSpan=5>Cumulative
(Aug. 28, 2012 to September 8, 2012)
</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported.
These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively.
</TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1>< 5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br2 bc1 bc7">0</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">0</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">0</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">0</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">0</TD><TD class=alignRight headers="br1 br2 bc8 bc14">0</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br3 bc1 bc7">0</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">0</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">0</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">0</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">0</TD><TD class=alignRight headers="br1 br3 bc8 bc14">0</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br4 bc1 bc7">0</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">0</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">0</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">0</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">0</TD><TD class=alignRight headers="br1 br4 bc8 bc14">0</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br5 bc1 bc7">0</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">0</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">0</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">0</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">0</TD><TD class=alignRight headers="br1 br5 bc8 bc14">0</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br6 bc1 bc7">0</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">0</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">0</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">0</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">0</TD><TD class=alignRight headers="br1 br6 bc8 bc14">0</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br7 bc1 bc7">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">0</TD><TD class=alignRight headers="br1 br7 bc8 bc14">0</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br8 bc1 bc7">0</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">0</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">0</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">0</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">0</TD><TD class=alignRight headers="br1 br8 bc8 bc14">0</TD></TR></TBODY></TABLE>

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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013

Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza strain characterizations

The National Microbiology Laboratory (NML) has not received any influenza virus specimens for strain characterization since the start of the 2012-2013 influenza season. However, of the influenza viruses characterized in the months of July and August 2012, the majority (52%) were antigenically similar to B/Wisconsin/01/2010 (Yamagata lineage) while the rest were antigenically similar to either A/Perth/16/2009 (24%) or B/Brisbane/60/2008 (Victoria lineage) (24%). The distribution of influenza strain characterizations for the 2011-2012 influenza season are presented in Figure 6.
Figure 6. Influenza strain characterizations, Canada, 2011-2012, N = 1, 443

Note: The recommended components for the 2011-2012 Northern Hemisphere influenza vaccine include: A/Perth/16/2009 (H3N2), A/California/7/2009 (H1N1) and B/Brisbane/60/2008.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral resistance

The National Microbiology Laboratory (NML) has not received any influenza virus specimens for antiviral resistance testing since the start of the 2012-2013 influenza season. However, antiviral resistance findings from the 2011-2012 influenza season are presented in Table 3.


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2011-2012</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">256</TD><TD class=alignRight headers="cr2 cc3">0</TD><TD class=alignRight headers="cr2 cc5">255</TD><TD class=alignRight headers="cr2 cc6">0</TD><TD class=alignRight headers="cr2 cc8">450</TD><TD class=alignRight headers="cr2 cc9">449 (99.8%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">256</TD><TD class=alignRight headers="cr3 cc3">0</TD><TD class=alignRight headers="cr3 cc5">256</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">356</TD><TD class=alignRight headers="cr3 cc9">356 (100%)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">967</TD><TD class=alignRight headers="cr4 cc3">0</TD><TD class=alignRight headers="cr4 cc5">967</TD><TD class=alignRight headers="cr4 cc6">0</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">1479</TD><TD class=alignRight headers="cr5 cc3">0</TD><TD class=alignRight headers="cr5 cc5">1478</TD><TD class=alignRight headers="cr5 cc6">0</TD><TD class=alignRight headers="cr5 cc8">806</TD><TD class=alignRight headers="cr5 cc9">805 (99.9%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national ILI consultation rate remained similar to the rates from two week prior and was 7.6 ILI consultations per 1,000 patient visits in week 35 and 5.6 per 1,000 visits in week 36; both rates were within the expected levels for this time of year (Figure 7). The highest consultation rates by age group were observed in those <5 years of age in both weeks (12.2/1,000 in week 35 and 18.1/1,000 in week 36.
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)

Note:No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)
Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)
No laboratory-confirmed influenza-associated paediatric (16 years of age and under) hospitalizations have been reported by the Immunization Monitoring Program Active (IMPACT) network since the start of the 2012-2013 influenza season.
Influenza Hospitalizations and Deaths (Aggregate Surveillance System)
No laboratory-confirmed influenza-associated hospitalizations, ICU admissions or deaths have been reported since the start of the 2012-2013 influenza season.
Note: Influenza-associated hospitalizations are not reported to PHAC by the following Provinces: BC, NU, QC, NS, & NB. Only hospitalizations that require intensive medical care are reported by SK. ICU admissions are not reported in ON.
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http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Weeks 31-32

FluWatch report: August 11 to August 24, 2013 (Weeks 33 & 34)

Posted 2013-08-30For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w34_13/pdf/fw2013-34-eng.pdf">FluWatch report: August 11 to August 24, 2013 (Weeks 33 & 34) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 289 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• Influenza activity in Canada remained at inter-seasonal levels during this 2-week period.
• The percentage of laboratory tests positive for all respiratory viruses decreased in weeks 33 and 34, with the number of tests low and similar to previous weeks.
• The ILI consultation rate was stable in recent weeks with a gradual downward trend, although it was above the average range in weeks 33 and 34.

NOTE: This is the final report for the 2012-2013 influenza season. The next FluWatch report will be the first for the 2013-2014 influenza season. Bi-weekly reports will continue until October 11, 2013. Laboratory detections reported through the Respiratory Virus Detection Surveillance System and influenza activity level maps continue to be updated weekly on the FluWatch website.

Influenza Activity (geographic spread) and Outbreaks

The number of regions reporting influenza activity was at inter-seasonal levels in weeks 33 and 34. In weeks 33 and 34, four regions reported sporadic activity (Figure 1). Localized activity has not been reported since week 26 (Figure 2). No new influenza outbreaks were reported in weeks 33 or 34 (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 34





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=58)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The overall percentage of positive influenza tests was low and stable, at 0.6% in week 33 and 0.3% in week 34. Among the nine influenza viruses detected in weeks 33 and 34, seven were influenza A (Table 1). Cumulative influenza virus detections by type/subtype to date are as follows: 85.1% influenza A [34.8% A(H3), 4.7% A(H1N1)pdm09 and 60.5% A(unsubtyped)] and 14.9% influenza B (Table 1).
Detailed information on age and type/subtype was complete for 26,123 cases (Table 2). The proportion of cases by age group is as follows: 14.8% <5 years; 10.4% between 5-19 years; 16.3% between 20-44 years; 17.0% between 45-64 years of age; 41.5% ≥65 years.
The percentage of positive tests for rhinovirus decreased during this 2-week period from 24.0% in week 32 to to 17.7% in week 34; although the number of positive tests was similar to previous weeks. The percentage of positive tests for parainfluenza declined slightly to 3.4% in week 34. The percentages of positive tests for other respiratory viruses were low in week 34: human metapneumovirus (hMPV) (0%), respiratory syncytial virus (RSV) (0.5%), coronavirus (0.6%) and adenovirus (2.1%) (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(August 11 to August 24, 2013)</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to August 24, 2013)</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">2</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1938</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1476</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">222</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">240</TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">407</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2363</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1771</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">448</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">144</TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">843</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">1</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">844</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">476</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">74</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">294</TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">325</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">660</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">79</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">571</TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">115</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">4</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">4</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">1</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8297</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3795</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">389</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4113</TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">954</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>
</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">1</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9823</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">36</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9241</TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1941</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>
</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1872</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">771</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">75</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1026</TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">102</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>
</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">388</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">8</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">215</TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">9</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>
</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">117</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">76</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">31</TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>
</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">718</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">240</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">2</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">476</TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">20</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">7</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">2</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">4</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">2</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">27020</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9395</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1274</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16351</TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">4717</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(August 11 to August 24, 2013)</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to August 24, 2013)</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively.</TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br2 bc1 bc7">0</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">3007</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">224</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">838</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1945</TD><TD class=alignRight headers="br1 br2 bc8 bc14">853</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br3 bc1 bc7">0</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1632</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">71</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">613</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">948</TD><TD class=alignRight headers="br1 br3 bc8 bc14">1080</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br4 bc1 bc7">1</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3540</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">358</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1223</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1959</TD><TD class=alignRight headers="br1 br4 bc8 bc14">731</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">1</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">1</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br5 bc1 bc7">0</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3734</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">330</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1224</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">2180</TD><TD class=alignRight headers="br1 br5 bc8 bc14">702</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">1</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br6 bc1 bc7">0</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">10002</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">138</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3719</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">6145</TD><TD class=alignRight headers="br1 br6 bc8 bc14">842</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br7 bc1 bc7">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">210</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">29</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">178</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">3</TD><TD class=alignRight headers="br1 br7 bc8 bc14">2</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">2</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">1</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br8 bc1 bc7">1</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">22125</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">1150</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">7795</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">13180</TD><TD class=alignRight headers="br1 br8 bc8 bc14">4210</TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza Strain Characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 1514 influenza viruses. The 662 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 250 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 464 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 138 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =1514

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral Resistance

During the 2012-13 season, NML has tested 1508 influenza viruses for resistance to oseltamivir, and 1505 influenza viruses for resistance to zanamivir. Among these, one A(H3N2) virus was resistant to oseltamivir and zanamivir, one A(H1N1)pdm09 virus was resistant to oseltamivir, and three influenza B virus samples were resistant to both oseltamivir and zanamivir. A total of 1344 influenza A viruses were tested for amantadine resistance and all but one A(H3N2) virus were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">653</TD><TD class=alignRight headers="cr2 cc3">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc5">653</TD><TD class=alignRight headers="cr2 cc6">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc8">1049</TD><TD class=alignRight headers="cr2 cc9">1048 (99.9%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">254</TD><TD class=alignRight headers="cr3 cc3">1 (0.4%)</TD><TD class=alignRight headers="cr3 cc5">251</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">295</TD><TD class=alignRight headers="cr3 cc9">295 (100%)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">601</TD><TD class=alignRight headers="cr4 cc3">3 (0.5%)</TD><TD class=alignRight headers="cr4 cc5">601</TD><TD class=alignRight headers="cr4 cc6">3 (0.5%)</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">1508</TD><TD class=alignRight headers="cr5 cc3">5 (0.3%)</TD><TD class=alignRight headers="cr5 cc5">1505</TD><TD class=alignRight headers="cr5 cc6">4 (0.3%)</TD><TD class=alignRight headers="cr5 cc8">1344</TD><TD class=alignRight headers="cr5 cc9">1343 (99.9%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate was similar between weeks 15 and 29, with an average of 16.2 ILI consultations per 1,000 patient visits (range 13.9 to 24.6). The rate continued a gradual downward trend in weeks 30-34, with an average of 12.3/1,000; and was 14.5/1,000 in week 34. The majority of weekly rates observed in weeks 18 to 34 were above the average range (Figure 7). The highest consultation rate was observed in children <5 years of age (41.7/1,000 visits) in week 33 and in children 5-19 years of age in week 34 (30.6/1,000 visits).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)

Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance


Paediatric Influenza Hospitalizations and Deaths (IMPACT)

One new laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalization was reported in week 34, a child <6 months of age with influenza A. No intensive care unit (ICU) admissions or deaths were reported by the Immunization Monitoring Program Active (IMPACT) network in weeks 33 and 34.

Since the start of the 2012-13 season, a total of 888 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 625 (70.4%) with influenza A [of which 124 (19.8%) were A(H3N2), 31 (5.0 %) were A(H1N1)pdm09 and the remaining 470 were A(unsubtyped); and 263 (29.6%) with influenza B. The distribution of cases by age group is as follows: 168 (18.9%) <6 months of age; 202 (22.7%) age 6-23 months; 254 (28.6 %) age 2-4 years; 189 (21.3%) age 5-9 years; and 75 (8.4%) age 10-16 years. Of the 888 cases, 110 (12.4%) were admitted to the ICU. Of the 92 ICU admissions with available data, 76 (82.6%) cases had at least one underlying condition. One death has been reported to date this season in a child 6-23 months of age with an underlying condition, with influenza B.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associated paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

Active surveillance of laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network concluded for the 2012-13 influenza season on April 30th, 2013. However, the PCIRN-SOS network continues to report limited data on laboratory-confirmed cases of influenza identified through passive surveillance at 15 out of 17 hospital sites. No new hospitalizations, ICU admissions or deaths were reported in weeks 33 and 34.

The cumulative data for the season to date includes data from active surveillance from November 4, 2012 to April 30, 2013 and data from passive surveillance since May 1, 2013. The cumulative number of cases is 1,812: 1,627 (89.8%) with influenza A [of which 313 were A(H3N2), 22 were A(H1N1)pdm09, and 1,292 were A(unsubtyped)]; 139 (7.7%) with influenza B, and the type has not been reported for 46 cases. The age distribution of hospitalizations is as follows: 1,230 (67.9%) were ≥65 years of age, 375 (20.7%) were 45-64 years, 195 (10.8%) were 20-44 years, and 12 (0.7%) were <20 years of age. ICU admission was required for 216 hospitalizations; the majority of which were adults ≥65 years of age (126; 58.3%). A total of 116 deaths have been reported: 26 with influenza A(H3N2), one with A(H1N1)pdm09, 82 with A(unsubtyped), 6 with influenza B, and one untyped. More than 85% of the deaths (99/116) were in adults ≥65 years of age, 14 (12.1%) were adults 45-64 years of age, and 3 (2.6%) were 20-44 years of age.

Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associated adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)
In weeks 33 and 34, two new laboratory-confirmed influenza-associated hospitalization was reported from participating provinces and territories*, both cases of influenza A in adults ≥65 years of age. To date this season, 5,077 influenza-associated hospitalizations have been reported, of which 86.3% have been influenza A. Of those subtyped (49.3%), influenza A(H3) was the predominant influenza strain. Age information was available for 5,074 cases, and the age distribution is as follows: 2,665 (52.5%) were ≥65 years of age; 843 (16.6%) were 45-64 years of age; 454 (8.9%) were 20-44 years of age; 41 (0.8%) were 15-19 years of age; 278 (5.5%) were 5-14 years; and 793 (15.6%) were 0-4 years of age. Of the 1,401 cases with available data, there have been 222 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults ≥65 years of age, followed by adults 45-64 years of age (36.0% and 33.8%, respectively). To date, 317 deaths have been reported: 258 adults ≥65 years of age, 37 adults 45-64 years; 13 adults 20-44 years, two children 5-14 years of age, and seven children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

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http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

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Re: Canada FluWatch Weekly Reports 2012-2013 Season Weeks 29-30

FluWatch report: July 28 to August 10, 2013 (Weeks 31 & 32)

Posted 2013-08-16For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w32_13/pdf/fw2013-32-eng.pdf">FluWatch report: July 28 to August 10, 2013 (Weeks 31 & 32) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• Influenza activity in Canada remained at inter-seasonal levels during this 2-week period.
• The percentage of tests positive for rhinovirus increased, while those of all other respiratory viruses were low. The percentage of laboratory tests positive for influenza was 0.4% in week 32.
• The ILI consultation rate was fairly stable, and above the expected range over weeks 18 to 31, and decreased in week 32.

Influenza Activity (geographic spread) and Outbreaks

The number of regions reporting influenza activity was at inter-seasonal levels in weeks 31 and 32. In weeks 31 and 32, one and two regions reported sporadic activity, respectively (Figure 1). No region has reported localized activity since week 26 (Figure 2). No new influenza outbreaks were reported in weeks 31 or 32 (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 32





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=58)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The overall percentage of positive influenza tests was low and stable, at 0.1% in week 31 and 0.4% in week 32. Among the five influenza viruses detected in weeks 31 and 32, all were influenza A (Table 1). Cumulative influenza virus detections by type/subtype to date are as follows: 85.1% influenza A [34.8% A(H3), 4.7% A(H1N1)pdm09 and 60.5% A(unsubtyped)] and 14.9% influenza B (Table 1).
Detailed information on laboratory detections of influenza was received for 26,329 cases to date this season. Data on age and type/subtype was complete for 26,117 cases (Table 2). The proportion of cases by age group is as follows: 14.8% <5 years; 10.4% between 5-19 years; 16.3% between 20-44 years; 17.0% between 45-64 years of age; 41.5% ≥65 years.
The percentage of positive tests for rhinovirus increased during this 2-week period from 15.2% in week 30 to 16.0% in week 31 and to 20.7% in week 32, although the number of positive tests was similar to previous weeks. The percentage of positive tests for parainfluenza has been stable at 4.5% for the past four weeks. The percentages of positive tests for other respiratory viruses were low in week 32: human metapneumovirus (hMPV) (0.4%), respiratory syncytial virus (RSV) (0.2%), coronavirus (0%) and adenovirus (1.8%) (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(July 28 to August 10, 2013)</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to August 10, 2013)</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">1 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">1 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1936 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1474 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">222 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">240 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">407 </TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2363 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1771 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">448 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">144 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">843 </TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">843 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">476 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">74 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">293 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">325 </TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">660 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">79 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">571 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">115 </TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">2 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">2 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8293 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3795 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">385 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4113 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">953 </TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>
</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">2 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">2 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9823 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">36 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9241 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1940 </TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>
</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1872 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">771 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">75 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1026 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">102 </TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>
</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">388 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">8 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">215 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">9 </TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>
</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">117 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">76 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">10 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">31 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1 </TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>
</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">718 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">240 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">2 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">476 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">20 </TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">5 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">2 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">1 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">2 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">27013 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9393 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1270 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16350 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">4715 </TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(July 28 to August 10, 2013)</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to August 10, 2013)</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively.</TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">0 </TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">0 </TD><TD class=alignRight headers="br1 br2 bc1 bc7">0 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">3007 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">224 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">838 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1945 </TD><TD class=alignRight headers="br1 br2 bc8 bc14">853 </TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">0 </TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">0 </TD><TD class=alignRight headers="br1 br3 bc1 bc7">0 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1632 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">71 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">613 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">948 </TD><TD class=alignRight headers="br1 br3 bc8 bc14">1080 </TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">1 </TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">1 </TD><TD class=alignRight headers="br1 br4 bc1 bc7">0 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3538 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">356 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1223 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1959 </TD><TD class=alignRight headers="br1 br4 bc8 bc14">730 </TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">2 </TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">1 </TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">1 </TD><TD class=alignRight headers="br1 br5 bc1 bc7">0 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3733 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">330 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1223 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">2180 </TD><TD class=alignRight headers="br1 br5 bc8 bc14">702 </TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">0 </TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">0 </TD><TD class=alignRight headers="br1 br6 bc1 bc7">0 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">10000 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">136 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3719 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">6145 </TD><TD class=alignRight headers="br1 br6 bc8 bc14">842 </TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc7">0 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">210 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">29 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">178 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">3 </TD><TD class=alignRight headers="br1 br7 bc8 bc14">2 </TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">3 </TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">1 </TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">2 </TD><TD class=alignRight headers="br1 br8 bc1 bc7">0 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">22120 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">1146 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">7794 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">13180 </TD><TD class=alignRight headers="br1 br8 bc8 bc14">4209 </TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza Strain Characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 1507 influenza viruses. The 657 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 248 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 464 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 138 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =1507

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral Resistance

During the 2012-13 season, NML has tested 1508 influenza viruses for resistance to oseltamivir, and 1505 influenza viruses for resistance to zanamivir. Among these, one A(H3N2) virus was resistant to oseltamivir and zanamivir, one A(H1N1)pdm09 virus was resistant to oseltamivir, and three influenza B virus samples were resistant to both oseltamivir and zanamivir. A total of 1341 influenza A viruses were tested for amantadine resistance and all but one A(H3N2) virus were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">653</TD><TD class=alignRight headers="cr2 cc3">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc5">653</TD><TD class=alignRight headers="cr2 cc6">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc8">1048</TD><TD class=alignRight headers="cr2 cc9">1047 (99.9%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">254</TD><TD class=alignRight headers="cr3 cc3">1 (0.4%)</TD><TD class=alignRight headers="cr3 cc5">251</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">293</TD><TD class=alignRight headers="cr3 cc9">293 (100%)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">601</TD><TD class=alignRight headers="cr4 cc3">3 (0.5%)</TD><TD class=alignRight headers="cr4 cc5">601</TD><TD class=alignRight headers="cr4 cc6">3 (0.5%)</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">1508</TD><TD class=alignRight headers="cr5 cc3">5 (0.3%)</TD><TD class=alignRight headers="cr5 cc5">1505</TD><TD class=alignRight headers="cr5 cc6">4 (0.3%)</TD><TD class=alignRight headers="cr5 cc8">1341</TD><TD class=alignRight headers="cr5 cc9">1340 (99.9%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate was similar between weeks 15 and 29, ranging from 13.9 to 24.6 ILI consultations per 1,000 patient visits. The rate increased from 10.0/1,000 in week 30 to 15.9/1,000 in week 31, but decreased to 8.5/1,000 in week 32. The rates observed in weeks 18 to 31 were above the expected range (Figure 7). The highest consultation rate was observed in children <5 years of age (39.7/1,000 visits) in week 31 and in children 5-19 years of age in week 32 (17.5/1,000 visits).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)

Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

No new laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalizations, intensive care unit (ICU) admissions or deaths were reported by the Immunization Monitoring Program Active (IMPACT) network in weeks 31 and 32.

Since the start of the 2012-13 season, a total of 886 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 623 (70.3%) with influenza A [of which 124 (19.9%) were A(H3N2), 29 (4.7 %) were A(H1N1)pdm09 and the remaining 470 were A(unsubtyped); and 263 (29.7%) with influenza B. The distribution of cases by age group is as follows: 165 (18.6%) <6 months of age; 203 (22.9%) age 6-23 months; 254 (28.7 %) age 2-4 years; 189 (21.3%) age 5-9 years; and 75 (8.5%) age 10-16 years. Of the 886 cases, 110 (12.4%) were admitted to the ICU. Of the 90 ICU admissions with available data, 74 (82.2%) cases had at least one underlying condition. One death has been reported to date this season in a child 6-23 months of age with an underlying condition, with influenza B.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associated paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.
Adult Influenza Hospitalizations and Deaths (PCIRN)
Active surveillance of laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network concluded for the 2012-13 influenza season on April 30th, 2013. However, the PCIRN-SOS network continues to report limited data on laboratory-confirmed cases of influenza identified through passive surveillance at 15 out of 17 hospital sites. Two hospitalizations were reported, one in each of weeks 31 and 32; both were cases of influenza A in patients 45-65 years of age. No ICU admissions or deaths were reported in weeks 31and 32.
The cumulative data for the season to date includes data from active surveillance from November 4, 2012 to April 30, 2013 and data from passive surveillance since May 1, 2013. The cumulative number of cases is 1,812: 1,627 (89.8%) with influenza A [of which 313 were A(H3N2), 22 were A(H1N1)pdm09, and 1,292 were A(unsubtyped)]; 139 (7.7%) with influenza B, and the type has not been reported for 46 cases. The age distribution of hospitalizations is as follows: 1,230 (67.9%) were ≥65 years of age, 375 (20.7%) were 45-64 years, 195 (10.8%) were 20-44 years, and 12 (0.7%) were <20 years of age. ICU admission was required for 216 hospitalizations; the majority of which were adults ≥65 years of age (126; 58.3%). A total of 116 deaths have been reported: 26 with influenza A(H3N2), one with A(H1N1)pdm09, 82 with A(unsubtyped), 6 with influenza B, and one untyped. More than 85% of the deaths (99/116) were in adults ≥65 years of age, 14 (12.1%) were adults 45-64 years of age, and 3 (2.6%) were 20-44 years of age.

Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associated adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)

In weeks 31 and 32, one new laboratory-confirmed influenza-associated hospitalization was reported from participating provinces and territories*, a case of influenza A in a child 1-4 years of age. To date this season, 5,075 influenza-associated hospitalizations have been reported, of which 86.3% have been influenza A. Of those subtyped (49.2%), influenza A(H3) was the predominant influenza strain. Age information was available for 5,072 cases, and the age distribution is as follows: 2,663 (52.5%) were ≥65 years of age; 843 (16.6%) were 45-64 years of age; 454 (9.0%) were 20-44 years of age; 41 (0.8%) were 15-19 years of age; 278 (5.5%) were 5-14 years; and 793 (15.6%) were 0-4 years of age. Of the 1,401 cases with available data, there have been 222 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults ≥65 years of age, followed by adults 45-64 years of age (36.0% and 33.8%, respectively). To date, 317 deaths have been reported: 258 adults ≥65 years of age, 37 adults 45-64 years; 13 adults 20-44 years, two children 5-14 years of age, and seven children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

.../
http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Weeks 29-30

FluWatch report: July 14 to 27, 2013 (Weeks 29 & 30)

Posted 2013-08-02For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w30_13/pdf/fw2013-30-eng.pdf">FluWatch report: July 14 to 27, 2013 (Weeks 29 & 30) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

»» Help with PDF documents

Overall Summary

• Influenza activity in Canada remained at inter-seasonal levels during this 2-week period.
• Detections of rhinovirus declined. Detections of all other respiratory viruses were low. The percentage of laboratory tests positive for influenza was 0.2% in week 30.
• The ILI consultation rate has been fairly stable over weeks 15 to 29, but decreased in week 30.

Influenza Activity (geographic spread) and Outbreaks

The number of regions reporting influenza activity was at inter-seasonal levels in weeks 29 and 30. No regions reported localized activity; in weeks 29 and 30, five and two regions reported sporadic activity, respectively (Figures 1 and 2). No new influenza outbreaks were reported in weeks 29 or 30 (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 30





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=58)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The overall percentage of positive influenza tests was low and stable, at 0.8% in week 29 and 0.2% in week 30. Among the 12 influenza viruses detected in weeks 29 and 30, nine were influenza A (Table 1). Cumulative influenza virus detections by type/subtype to date are as follows: 85.1% influenza A [34.8% A(H3), 4.7% A(H1N1)pdm09 and 60.5% A(unsubtyped)] and 14.9% influenza B (Table 1).
Detailed information on laboratory detections of influenza was received for 26,324 cases to date this season. Data on age and type/subtype was complete for 26,112 cases (Table 2). The proportion of cases by age group is as follows: 14.8% <5 years; 10.4% between 5-19 years; 16.3% between 20-44 years; 17.0% between 45-64 years of age; 41.5% ≥65 years.
The percentage of positive tests for rhinovirus decreased from its peak of 25.6% in week 26 to 19.4% in week 29 and to 11.0% in week 30. The percentage of positive tests for parainfluenza was stable at 4.5% in weeks 29 and 30. The percentages of positive tests for other respiratory viruses were low in week 30: human metapneumovirus (hMPV) (0.7%), respiratory syncytial virus (RSV) (0.8%), coronavirus (0.2%) and adenovirus (2.2%) (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(July 14 to July 27, 2013)</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to July 27, 2013)</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">4</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">3</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1935</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1473</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">221</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">241</TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">407</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2363</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1771</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">448</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">144</TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">843</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">1</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">1</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">843</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">476</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">74</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">293</TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">325</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">1</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">660</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">79</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">571</TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">115</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">3</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">2</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8291</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3793</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">385</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4113</TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">953</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>
</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">1</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">1</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9821</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">36</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9239</TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1940</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>
</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1872</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">771</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">75</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1026</TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">102</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>
</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">388</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">8</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">215</TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">9</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>
</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">117</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">76</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">31</TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>
</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">718</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">240</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">2</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">476</TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">20</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">9</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">5</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">4</TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">3</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">27008</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9390</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1269</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16349</TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">4715</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(July 14 to July 27, 2013)</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to July 27, 2013)</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively.</TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">1</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">1</TD><TD class=alignRight headers="br1 br2 bc1 bc7">0</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">3007</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">224</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">838</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1945</TD><TD class=alignRight headers="br1 br2 bc8 bc14">853</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br3 bc1 bc7">0</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1632</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">71</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">613</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">948</TD><TD class=alignRight headers="br1 br3 bc8 bc14">1080</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br4 bc1 bc7">0</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3537</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">356</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1223</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1958</TD><TD class=alignRight headers="br1 br4 bc8 bc14">730</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">3</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">2</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">1</TD><TD class=alignRight headers="br1 br5 bc1 bc7">0</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3731</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">329</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1223</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">2179</TD><TD class=alignRight headers="br1 br5 bc8 bc14">702</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">2</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">1</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">1</TD><TD class=alignRight headers="br1 br6 bc1 bc7">1</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">9998</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">136</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3716</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">6146</TD><TD class=alignRight headers="br1 br6 bc8 bc14">842</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br7 bc1 bc7">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">210</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">29</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">178</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">3</TD><TD class=alignRight headers="br1 br7 bc8 bc14">2</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">6</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">3</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">3</TD><TD class=alignRight headers="br1 br8 bc1 bc7">1</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">22115</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">1145</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">7791</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">13179</TD><TD class=alignRight headers="br1 br8 bc8 bc14">4209</TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza Strain Characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 1499 influenza viruses. The 654 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 245 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 462 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 138 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =1499

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral Resistance

During the 2012-13 season, NML has tested 1495 influenza viruses for resistance to oseltamivir, and 1492 influenza viruses for resistance to zanamivir. Among these, one A(H3N2) virus was resistant to oseltamivir and zanamivir, one A(H1N1)pdm09 virus was resistant to oseltamivir, and three influenza B virus samples were resistant to both oseltamivir and zanamivir. A total of 1334 influenza A viruses were tested for amantadine resistance and all but one A(H3N2) virus were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">648</TD><TD class=alignRight headers="cr2 cc3">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc5">648</TD><TD class=alignRight headers="cr2 cc6">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc8">1044</TD><TD class=alignRight headers="cr2 cc9">1043 (99.9%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">251</TD><TD class=alignRight headers="cr3 cc3">1 (0.4%)</TD><TD class=alignRight headers="cr3 cc5">248</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">290</TD><TD class=alignRight headers="cr3 cc9">290 (100%)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">596</TD><TD class=alignRight headers="cr4 cc3">3 (0.5%)</TD><TD class=alignRight headers="cr4 cc5">596</TD><TD class=alignRight headers="cr4 cc6">3 (0.5%)</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">1495</TD><TD class=alignRight headers="cr5 cc3">5 (0.3%)</TD><TD class=alignRight headers="cr5 cc5">1492</TD><TD class=alignRight headers="cr5 cc6">4 (0.3%)</TD><TD class=alignRight headers="cr5 cc8">1334</TD><TD class=alignRight headers="cr5 cc9">1333 (99.9%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate was similar between weeks 15 and 29, ranging from 13.9 to 24.6 ILI consultations per 1,000 patient visits, but the rate decreased to 10.0/1,000 in week 30. The rates observed in weeks 18 to 30 were above the expected range (Figure 7). The highest consultation rate was observed in children 5-19 years of age in both weeks 29 (28.7/1,000 visits) and 30 (20.0/1,000 visits).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)

Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)
In week 29, one laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalization was reported by the Immunization Monitoring Program Active (IMPACT) network, in a child <6 months of age with influenza A. No hospitalizations were reported in week 30. No intensive care unit (ICU) admissions or deaths were reported during weeks 29 and 30.

Since the start of the 2012-13 season, a total of 885 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 623 (70.4%) with influenza A [of which 124 (19.9%) were A(H3N2), 29 (4.7 %) were A(H1N1)pdm09 and the remaining 470 were A(unsubtyped); and 262 (29.6%) with influenza B. The distribution of cases by age group is as follows: 164 (18.5%) <6 months of age; 203 (22.9%) age 6-23 months; 254 (28.7 %) age 2-4 years; 189 (21.4%) age 5-9 years; and 75 (8.5%) age 10-16 years. Of the 885 cases, 110 (12.4%) were admitted to the ICU. Of the 82 ICU admissions with available data, 68 (82.9%) cases had at least one underlying condition. One death has been reported to date this season in a child 6-23 months of age with an underlying condition, with influenza B.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associated paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

Active surveillance of laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network concluded for the 2012-13 influenza season on April 30th, 2013. However, the PCIRN-SOS network continues to report limited data on laboratory-confirmed cases of influenza identified through passive surveillance at 15 out of 17 hospital sites. No hospitalizations, ICU admissions or deaths were reported in week 29 or 30.

The cumulative data for the season to date includes data from active surveillance from November 4, 2012 to April 30, 2013 and data from passive surveillance since May 1, 2013. The cumulative number of cases is 1,810: 1,625 (89.8%) with influenza A [of which 312 were A(H3N2), 21 were A(H1N1)pdm09, and 1,292 were A(unsubtyped)]; 139 (7.7%) with influenza B, and the type has not been reported for 46 cases. The age distribution of hospitalizations is as follows: 1,230 (68.0%) were ≥65 years of age, 373 (20.6%) were 45-64 years, 195 (10.7%) were 20-44 years, and 12 (0.7%) were <20 years of age. ICU admission was required for 216 hospitalizations; the majority of which were adults ≥65 years of age (123; 56.9%). A total of 116 deaths have been reported: 26 with influenza A(H3N2), one with A(H1N1)pdm09, 82 with A(unsubtyped), 6 with influenza B, and one untyped. More than 85% of the deaths (99/116) were in adults ≥65 years of age, 14 (12.1%) were adults 45-64 years of age, and 3 (2.6%) were 20-44 years of age.
Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associated adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)
In weeks 29 and 30, one new laboratory-confirmed influenza-associated hospitalization was reported from participating provinces and territories*. To date this season, 5,074 influenza-associated hospitalizations have been reported, of which 86.3% have been influenza A. Of those subtyped (49.2%), influenza A(H3) was the predominant influenza strain. Age information was available for 5,071 cases, and the age distribution is as follows: 2,663 (52.5%) were ≥65 years of age; 843 (16.6%) were 45-64 years of age; 454 (9.0%) were 20-44 years of age; 41 (0.8%) were 15-19 years of age; 278 (5.5%) were 5-14 years; and 792 (15.6%) were 0-4 years of age. Of the 1,401 cases with available data, there have been 222 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults ≥65 years of age, followed by adults 45-64 years of age (36.0% and 33.8%, respectively). To date, 317 deaths have been reported: 258 adults ≥65 years of age, 37 adults 45-64 years; 13 adults 20-44 years, two children 5-14 years of age, and seven children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

.../
http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Weeks 25-26

FluWatch report: June 16 to 29, 2013 (Weeks 25 & 26)

Posted 2013-07-05For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w26_13/pdf/fw2013-26-eng.pdf">FluWatch report: June 16 to 29, 2013 (Weeks 25 & 26) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• Influenza activity in Canada continued to decline, with only one region reporting localized activity during this 2-week period.
• Detections of rhinovirus continued to follow an overall upward trend. Detections of most other respiratory viruses declined. The percentage of laboratory tests positive for influenza was 0.7% in week 26.
• The ILI consultation rate has been fairly stable over the past 12 weeks, and has been above the expected range for the past nine weeks.

Influenza Activity (geographic spread) and Outbreaks

The number of regions reporting influenza activity was at inter-seasonal levels in weeks 25 and 26. In week 25, eight regions reported sporadic activity. In week 26, Yukon reported localized activity and six regions reported sporadic activity (Figures 1 and 2). One new influenza outbreak in a long-term-care facility was reported in week 26 (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 26





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=58)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The overall percentage of positive influenza tests continued to decrease, and was 0.8% in week 25 and 0.7% in week 26. Among the 23 influenza viruses detected in weeks 25 & 26, 13 were influenza A (Table 1). Cumulative influenza virus detections by type/subtype to date are as follows: 85.1% influenza A [34.4% A(H3), 4.7% A(H1N1)pdm09 and 60.9% A(unsubtyped)] and 14.9% influenza B (Table 1).
Detailed information on laboratory detections of influenza was received for 26,300 cases to date this season. Data on age and type/subtype was complete for 26,088 cases (Table 2).The proportion of cases by age group is as follows: 14.8% <5 years; 10.4% between 5-19 years; 16.3% between 20-44 years; 17.0% between 45-64 years of age; 41.5% ≥65 years.
The percentage of positive tests for rhinovirus continued to follow the upward trend observed since week 01, and was 24.8% in week 25 and decreased slightly to 22.9% in week 26. The percentage of positive tests for parainfluenza increased from 4.7% in week 25 to 6.5% in week 26, interrupting the downward trend observed over the previous six weeks. The percentage of positive tests for human metapneumovirus (hMPV) increased slightly to 2.6% in week 26, but continued to follow a downward trend. The percentages of positive tests for respiratory syncytial virus (RSV) (1.1%), coronavirus (0.8%) and adenovirus (1.4%) were low in weeks 25 and 26 (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(June 16 to June 29, 2013)
</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to June 29, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B
</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B
</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*
</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*
</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">7</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">5</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1923</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1462</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">220</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">241</TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">407</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">3</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2363</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1771</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">448</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">144</TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">844</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">1</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">840</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">476</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">74</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">290</TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">324</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">659</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">79</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">570</TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">114</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">3</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">1</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">1</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">4</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8285</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3791</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">383</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4111</TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">952</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>

</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">1</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9817</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">36</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9235</TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1939</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>

</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">2</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1872</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">771</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">75</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1026</TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">102</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>

</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">388</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">8</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">215</TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">9</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>

</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">117</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">76</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">31</TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>

</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">719</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">152</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">567</TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">18</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">13</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">6</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">1</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">6</TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">10</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">26983</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9289</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1264</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16430</TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">4710</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(June 16 to June 29, 2013)
</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to June 29, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively. </TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br2 bc1 bc7">0</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">3005</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">223</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">838</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1944</TD><TD class=alignRight headers="br1 br2 bc8 bc14">852</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br3 bc1 bc7">3</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1631</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">71</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">613</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">947</TD><TD class=alignRight headers="br1 br3 bc8 bc14">1080</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">2</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">1</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">1</TD><TD class=alignRight headers="br1 br4 bc1 bc7">0</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3533</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">355</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1219</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1959</TD><TD class=alignRight headers="br1 br4 bc8 bc14">730</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">5</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">3</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">2</TD><TD class=alignRight headers="br1 br5 bc1 bc7">0</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3724</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">327</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1219</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">2178</TD><TD class=alignRight headers="br1 br5 bc8 bc14">702</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">3</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">2</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br6 bc1 bc7">0</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">9990</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">136</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3711</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">6143</TD><TD class=alignRight headers="br1 br6 bc8 bc14">841</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br7 bc1 bc7">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">210</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">29</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">178</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">3</TD><TD class=alignRight headers="br1 br7 bc8 bc14">2</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">10</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">6</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">3</TD><TD class=alignRight headers="br1 br8 bc1 bc7">3</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">22093</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">1141</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">7778</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">13174</TD><TD class=alignRight headers="br1 br8 bc8 bc14">4207</TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza Strain Characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 1453 influenza viruses. The 644 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 243 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 439 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 127 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =1453

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral Resistance

During the 2012-13 season, NML has tested 1422 influenza viruses for resistance to oseltamivir, and 1419 influenza viruses for resistance to zanamivir. Among these, one A(H3N2) virus was resistant to oseltamivir and zanamivir, one A(H1N1)pdm09 virus was resistant to oseltamivir, and one influenza B virus was resistant to both oseltamivir and zanamivir. A total of 1312 influenza A viruses were tested for amantadine resistance and all but one A(H3N2) virus were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">639</TD><TD class=alignRight headers="cr2 cc3">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc5">639</TD><TD class=alignRight headers="cr2 cc6">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc8">1031</TD><TD class=alignRight headers="cr2 cc9">1030 (99.9%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">242</TD><TD class=alignRight headers="cr3 cc3">1 (0.4%)</TD><TD class=alignRight headers="cr3 cc5">239</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">281</TD><TD class=alignRight headers="cr3 cc9">281 (100%)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">541</TD><TD class=alignRight headers="cr4 cc3">1 (0.2%)</TD><TD class=alignRight headers="cr4 cc5">541</TD><TD class=alignRight headers="cr4 cc6">1 (0.2%)</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">1422</TD><TD class=alignRight headers="cr5 cc3">3 (0.2%)</TD><TD class=alignRight headers="cr5 cc5">1419</TD><TD class=alignRight headers="cr5 cc6">2 (0.1%)</TD><TD class=alignRight headers="cr5 cc8">1312</TD><TD class=alignRight headers="cr5 cc9">1311 (99.9%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate has been similar for the past twelve weeks, ranging from 14.3 to 24.4 ILI consultations per 1,000 patient visits, and was 19.3/1,000 in week 26. The rates observed in weeks 18 to 26 were above the expected range (Figure 7). The highest consultation rate was observed in children 5-19 years of age (30.1/1,000 visits) in week 25, and in children under 5 years of age (49.0/1,000 visits) in week 26.
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)



Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

In week 25, one laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalization of influenza B in a child 5-9 years of age was reported by the Immunization Monitoring Program Active (IMPACT) network. No cases were reported in week 26. No admissions to an intensive care unit (ICU) and no deaths were reported in weeks 25 and 26.

Since the start of the 2012-13 season, a total of 883 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 623 (70.6%) with influenza A [of which 124 (19.9%) were A(H3N2), 27 (4.3%) were A(H1N1)pdm09 and the remaining 472 were A(unsubtyped); and 260 (29.4%) with influenza B. The distribution of cases by age group is as follows: 162 (18.3%) <6 months of age; 204 (23.1%) age 6-23 months; 252 (28.5%) age 2-4 years; 190 (21.5%) age 5-9 years; and 75 (8.5%) age 10-16 years. Of the 883 cases, 102 (11.6%) were admitted to the ICU. Of the 78 ICU admissions with available data, 65 (83.3%) cases had at least one underlying condition. One death has been reported to date this season in a child 6-23 months of age with an underlying condition, with influenza B.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associated paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

Active surveillance of laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network concluded for the 2012-13 influenza season on April 30th, 2013. However, the PCIRN-SOS network continues to report limited data on laboratory-confirmed cases of influenza identified through passive surveillance at 15 out of 17 hospital sites. In weeks 25 and 26, no hospitalizations, ICU admissions or deaths were reported.

The cumulative data for the season to date includes data from active surveillance from November 4, 2012 to April 30, 2013 and data from passive surveillance since May 1, 2013. The cumulative number of cases is 1,809: 1,624 (89.8%) with influenza A [of which 312 were A(H3N2), 20 were A(H1N1)pdm09, and 1,292 were A(unsubtyped)]; 139 (7.7%) with influenza B, and the type has not been reported for 46 cases. The age distribution of hospitalizations is as follows: 1,230 (68.0%) were ≥65 years of age, 373 (20.6%) were 45-64 years, 194 (10.7%) were 20-44 years, and 12 (0.7%) were <20 years of age. ICU admission was required for 216 hospitalizations; the majority of which were adults ≥65 years of age (123; 56.9%). A total of 116 deaths have been reported: 26 with influenza A(H3N2), one with A(H1N1)pdm09, 82 with A(unsubtyped), 6 with influenza B, and one untyped. More than 85% of the deaths (99/116) were in adults ≥65 years of age, 14 (12.1%) were adults 45-64 years of age, and 3 (2.6%) were 20-44 years of age.

Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associated adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)

In weeks 25 and 26, 11 laboratory-confirmed influenza-associated hospitalizations were reported from six of the eight participating provinces and territories<SUP>*</SUP>. The majority of cases were influenza A (63.6%). Four hospitalizations were adults ≥65 years of age, two 45-64 years of age, two 20-44 years of age, two 5-14 years of age and one child 0-4 years of age. There was one ICU admission reported among the four cases with available data: a case of influenza A(H3) in an adult ≥65 years of age. Two deaths were reported in adults ≥65 years of age: one case of influenza A(H3) and one case of influenza A(unsubtyped).

To date this season, 5,053 influenza-associated hospitalizations have been reported, of which 86.4% have been influenza A. Of those subtyped (49.3%), influenza A(H3) was the predominant influenza strain. Age information was available for 5,050 cases, and the age distribution is as follows: 2,657 (52.6%) were ≥65 years of age; 838 (16.6%) were 45-64 years of age; 452 (9.0%) were 20-44 years of age; 41 (0.8%) were 15-19 years of age; 275 (5.4%) were 5-14 years; and 787 (15.6%) were 0-4 years of age. Of the 1,401 cases with available data, there have been 222 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults ≥65 years of age, followed by adults 45-64 years of age (35.0% and 33.8%, respectively). To date, 314 deaths have been reported: 258 adults ≥65 years of age, 36 adults 45-64 years; 12 adults 20-44 years, one child 5-14 years of age, and seven children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

.../
http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Weeks 23-24

FluWatch report: June 2 to 15, 2013 (Weeks 23 & 24)

Posted 2013-06-21For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w24_13/pdf/fw2013-24-eng.pdf">FluWatch report: June 2 to 15, 2013 (Weeks 23 & 24) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• Influenza activity in Canada continued to decline, with only one region reporting localized activity during this 2-week period.
• Detections of rhinovirus continued to follow an overall upward trend, while detections of other respiratory viruses decreased. The percentage of laboratory tests positive for influenza was 1.1% in week 24.
• The ILI consultation rate has been fairly stable over the past 10 weeks, and has been above the expected range for the past seven weeks.

Influenza Activity (geographic spread) and Outbreaks

The number of regions reporting influenza activity continued to decrease in weeks 23 and 24. In week 23, one region in Quebec reported localized activity and 15 regions reported sporadic activity. In week 24, no region reported localized activity and 8 regions reported sporadic activity (Figures 1 and 2). One new influenza outbreak in a long-term-care facility was reported in week 23 (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 24





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=58)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The overall percentage of positive influenza tests continued to decrease, and was 2.0% in week 23 and 1.1% in week 24. Among the influenza viruses detected in weeks 23 & 24 (n=53), 75.5% were positive for influenza B viruses; all influenza A viruses were either A(H3) or A(unsubtyped) (Table 1). Cumulative influenza virus detections by type/subtype to date are as follows: 85.2% influenza A [34.4% A(H3), 4.7% A(H1N1)pdm09 and 60.9% A(unsubtyped)] and 14.8% influenza B (Table 1).
Detailed information on laboratory detections of influenza was received for 26,276 cases to date this season. Data on age and type/subtype was complete for 26,064 cases (Table 2). The proportion of cases by age group is as follows: 14.8% <5 years; 10.4% between 5-19 years; 16.3% between 20-44 years; 17.0% between 45-64 years of age; 41.5% ≥65 years.
The percentage of positive tests for rhinovirus continued the upward trend observed since week 01, and was 20.7% in week 23 and 18.9% in week 24. The percentage of positive tests for all other viruses decreased over weeks 23 and 24: parainfluenza (5.2%), respiratory syncytial virus (RSV) (1.2%), human metapneumovirus (hMPV) (1.7%) and coronavirus (0.6%) (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(June 2 to June 15, 2013)</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to June 15, 2013)</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">1 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">1 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">2 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1916 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1457 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">220 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">239 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">407 </TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">12 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2363 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1771 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">448 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">144 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">840 </TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">2 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">839 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">476 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">74 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">289 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">323 </TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">2 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">659 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">79 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">570 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">114 </TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">8 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">6 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">2 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">10 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8282 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3790 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">382 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4110 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">948 </TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>
</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">4 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">4 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">7 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9815 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">36 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9233 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1938 </TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>
</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">5 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1872 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">771 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">75 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1026 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">100 </TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>
</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">388 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">8 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">215 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">9 </TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>
</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">117 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">76 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">10 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">31 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1 </TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>
</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">719 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">152 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">0 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">567 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">18 </TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">13 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">7 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">6 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">40 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">26970 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9283 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1263 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16424 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">4698 </TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(June 2 to June 15, 2013)</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to June 15, 2013)</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively. </TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">0 </TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">0 </TD><TD class=alignRight headers="br1 br2 bc1 bc7">4 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">3004 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">223 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">838 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1943 </TD><TD class=alignRight headers="br1 br2 bc8 bc14">849 </TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">0 </TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">0 </TD><TD class=alignRight headers="br1 br3 bc1 bc7">8 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1631 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">71 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">613 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">947 </TD><TD class=alignRight headers="br1 br3 bc8 bc14">1076 </TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">1 </TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">1 </TD><TD class=alignRight headers="br1 br4 bc1 bc7">2 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3529 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">355 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1215 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1959 </TD><TD class=alignRight headers="br1 br4 bc8 bc14">728 </TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">3 </TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">1 </TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">2 </TD><TD class=alignRight headers="br1 br5 bc1 bc7">2 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3719 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">327 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1216 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">2176 </TD><TD class=alignRight headers="br1 br5 bc8 bc14">702 </TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">1 </TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">1 </TD><TD class=alignRight headers="br1 br6 bc1 bc7">2 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">9985 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">135 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3708 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">6142 </TD><TD class=alignRight headers="br1 br6 bc8 bc14">841 </TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc7">0 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">210 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">29 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">178 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">3 </TD><TD class=alignRight headers="br1 br7 bc8 bc14">2 </TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">5 </TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">1 </TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">4 </TD><TD class=alignRight headers="br1 br8 bc1 bc7">18 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">22078 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">1140 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">7768 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">13170 </TD><TD class=alignRight headers="br1 br8 bc8 bc14">4198 </TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza Strain Characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 1396 influenza viruses. The 640 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 229 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 409 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 118 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =1396

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral Resistance

During the 2012-13 season, NML has tested 1378 influenza viruses for resistance to oseltamivir, and 1375 influenza viruses for resistance to zanamivir. Among these, one A(H3N2) virus was resistant to oseltamivir and zanamivir and one A(H1N1)pdm09 virus was resistant to oseltamivir. A total of 1285 influenza A viruses were tested for amantadine resistance and all but one A(H3N2) virus were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">628</TD><TD class=alignRight headers="cr2 cc3">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc5">628</TD><TD class=alignRight headers="cr2 cc6">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc8">1018</TD><TD class=alignRight headers="cr2 cc9">1017 (99.9%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">229</TD><TD class=alignRight headers="cr3 cc3">1 (0.4%)</TD><TD class=alignRight headers="cr3 cc5">226</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">267</TD><TD class=alignRight headers="cr3 cc9">267 (100%)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">521</TD><TD class=alignRight headers="cr4 cc3">0</TD><TD class=alignRight headers="cr4 cc5">521</TD><TD class=alignRight headers="cr4 cc6">0</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">1378</TD><TD class=alignRight headers="cr5 cc3">2 (0.1%)</TD><TD class=alignRight headers="cr5 cc5">1375</TD><TD class=alignRight headers="cr5 cc6">1 (0.1%)</TD><TD class=alignRight headers="cr5 cc8">1285</TD><TD class=alignRight headers="cr5 cc9">1284 (99.9%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate has been similar for the past ten weeks, ranging from 14.3 to 24.4 ILI consultations per 1,000 patient visits, and was 14.4/1,000 in week 24. The rates observed in weeks 18 to 24 were above the expected range (Figure 7). The highest consultation rate was observed in children 5-19 years of age (48.2/1,000 visits) in week 23, and in children under 5 years of age (16.8/1,000 visits) in week 24.
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)



Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

In weeks 23 and 24, three laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalizations were reported by the Immunization Monitoring Program Active (IMPACT) network. Two cases of influenza B: one in a child <6 months of age, and the other in a child 10-16 years of age; and one case of influenza A(unsubtyped) in a child 5-9 years of age were reported. No admissions to an intensive care unit (ICU) and no deaths were reported during weeks 23 and 24.

Since the start of the 2012-13 season, a total of 880 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 624 (70.9%) with influenza A [of which 124 (19.9%) were A(H3N2), 27 (4.3%) were A(H1N1)pdm09 and the remaining 473 were A(unsubtyped); and 256 (29.1%) with influenza B. The distribution of cases by age group is as follows: 162 (18.4%) <6 months of age; 202 (23.0%) age 6-23 months; 253 (28.8%) age 2-4 years; 188 (21.4%) age 5-9 years; and 75 (8.5%) age 10-16 years. Of the 880 cases, 99 (11.3%) were admitted to the ICU. Of the 76 ICU admissions with available data, 63 (82.9%) cases had at least one underlying condition. One death has been reported to date this season in a child 6-23 months of age with an underlying condition, with influenza B.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associated paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

Active surveillance of laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network concluded for the 2012-13 influenza season on April 30th, 2013. However, the PCIRN-SOS network continues to report limited data on laboratory-confirmed cases of influenza identified through passive surveillance at 15 out of 17 hospital sites. In weeks 23 and 24, no hospitalizations, ICU admissions or deaths were reported.

The cumulative data for the season to date includes data from active surveillance from November 4, 2012 to April 30, 2013 and data from passive surveillance since May 1, 2013. The cumulative number of cases is 1,809: 1,624 (89.8%) with influenza A [of which 312 were A(H3N2), 20 were A(H1N1)pdm09, and 1,292 were A(unsubtyped)]; 139 (7.7%) with influenza B, and the type has not been reported for 46 cases. The age distribution of hospitalizations is as follows: 1,230 (68.0%) were ≥65 years of age, 373 (20.6%) were 45-64 years, 194 (10.7%) were 20-44 years, and 12 (0.7%) were <20 years of age. ICU admission was required for 216 hospitalizations; the majority of which were adults ≥65 years of age (123; 56.9%). A total of 116 deaths have been reported: 26 with influenza A(H3N2), one with A(H1N1)pdm09, 82 with A(unsubtyped), 6 with influenza B, and one untyped. More than 85% of the deaths (99/116) were in adults ≥65 years of age, 14 (12.1%) were adults 45-64 years of age, and 3 (2.6%) were 20-44 years of age.

Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associated adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)

In weeks 23 and 24, 45 laboratory-confirmed influenza-associated hospitalizations were reported from participating provinces and territories*. The majority of cases were influenza B (51.1%). The highest proportion of hospitalisations was adults ≥65 years of age (44.4%), followed by adults 45-64 years of age (24.4%). There were no ICU admissions reported among the four cases with available data. Two deaths were reported: one case of influenza A(H3) in an adult aged 20-44 years, and one case of influenza B in an adult ≥65 years of age.

To date this season, 5,042 influenza-associated hospitalizations have been reported, of which 86.4% have been influenza A. Of those subtyped (49.3%), influenza A(H3) was the predominant influenza strain. Age information was available for 5,039 cases, and the age distribution is as follows: 2,653 (52.6%) were ≥65 years of age; 836 (16.6%) were 45-64 years of age; 450 (8.9%) were 20-44 years of age; 41 (0.8%) were 15-19 years of age; 273 (5.4%) were 5-14 years; and 786 (15.6%) were 0-4 years of age. Of the 1,397 cases with available data, there have been 221 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults ≥65 years of age, followed by adults 45-64 years of age (35.8% and 33.9%, respectively). To date, 312 deaths have been reported: 256 adults ≥65 years of age, 36 adults 45-64 years; 12 adults 20-44 years, one child 5-14 years of age, and seven children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

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http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Week 20

FluWatch report: May 12 to May 18, 2013 (Week 20)

Posted 2013-05-24For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w20_13/pdf/fw2013-20-eng.pdf">FluWatch report: May 12 to May 18, 2013 (Week 20) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• Influenza activity in Canada continued its slow decline in week 20, with the percentage of laboratory tests positive for influenza at 6.7%. Influenza B was the predominant type, and detections continued to decrease.
• Detections of rhinovirus and parainfluenza continued to increase slowly, while detections of most other respiratory viruses were stable or decreasing in week 20.
• The ILI consultation rate decreased and was within the expected range. The number of regions reporting localized activity was similar to previous weeks.

Note: This is the final weekly report for the 2012-13 influenza season. Bi-weekly reports will commence on June 7th (for weeks 21 and 22). However, laboratory detections reported through the RVDSS and influenza activity level maps will be updated weekly on the FluWatch website.

Influenza Activity (geographic spread) and Outbreaks

In week 20, six regions [AB(1), MB(1), ON(3), NB(1)] reported localized activity and 21 regions reported sporadic activity. The number of regions reporting localized activity has been similar for the past three weeks (Figures 1 and 2). Three new influenza outbreaks were reported, all in long-term-care facilities (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 20





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=58)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The overall percentage of positive influenza tests continued to decrease, from 8.4% in week 19 to 6.7% in week 20. Detections of influenza B decreased, and represented 80.1% of total positive influenza detections in week 20 (Figure 4). Among the influenza viruses detected in week 20 (n=161), 19.9% were positive for influenza A viruses [of which 28.1% were A(H1N1)pdm09, 18.8% were A(H3), and 53.1% were A(unsubtyped)] (Table 1). Cumulative influenza virus detections by type/subtype to date are as follows: 85.6% influenza A [34.4% A(H3), 4.6% A(H1N1)pdm09 and 60.9% A(unsubtyped)] and 14.4% influenza B (Table 1).
Detailed information on age and type/subtype has been received for 24,026 cases to date this season (Table 2). The proportion of cases by age group is as follows: 14.2% <5 years; 10.0% between 5-19 years; 15.8% between 20-44 years; 17.0% between 45-64 years of age; 43.0% ≥65 years.
The percentage of positive tests for rhinovirus increased slightly from 16.8% in week 19 to 17.2% in week 20, continuing its upward trend since week 01. The percentage of positive tests for parainfluenza (7.7%) also continued the gradual increase observed since week 08. The percentage of tests positive for respiratory syncytial virus (RSV) (2.4%) continued its decline from a peak in week 08. The percentages of positive tests for human metapneumovirus (hMPV) (4.2%) and coronavirus (1.2%) were stable in week 20 (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(May 12 to May 18, 2013)
</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to May 18, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B
</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B
</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*
</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*
</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">5 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">2 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">1 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">2 </TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">13 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1913 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1453 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">219 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">241 </TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">413 </TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">3 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">3 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">20 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2358 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1770 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">444 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">144 </TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">806 </TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">3 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">1 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">2 </TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">8 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">839 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">476 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">74 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">289 </TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">306 </TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">1 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">1 </TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">4 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">659 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">79 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">570 </TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">104 </TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">11 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">4 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">3 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">4 </TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">31 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8268 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3784 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">377 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4107 </TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">912 </TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>

</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">3 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">3 </TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">38 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9805 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">36 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9223 </TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1898 </TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>

</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">5 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">5 </TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">15 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1868 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">771 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">73 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1024 </TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">86 </TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>

</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">388 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">8 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">215 </TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">7 </TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>

</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">1 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">1 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">117 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">76 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">10 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">31 </TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1 </TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>

</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">0 </TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">0 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">718 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">152 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">0 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">566 </TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">16 </TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">32 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">6 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">9 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">17 </TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">129 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">26933 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9272 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1251 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16410 </TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">4549 </TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(May 12 to May 18, 2013)
</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to May 18, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively. </TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">6 </TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">3 </TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">1 </TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">2 </TD><TD class=alignRight headers="br1 br2 bc1 bc7">10 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">2662 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">220 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">840 </TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1602 </TD><TD class=alignRight headers="br1 br2 bc8 bc14">751 </TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">1 </TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">1 </TD><TD class=alignRight headers="br1 br3 bc1 bc7">11 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1446 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">71 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">623 </TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">752 </TD><TD class=alignRight headers="br1 br3 bc8 bc14">961 </TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">1 </TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">1 </TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">0 </TD><TD class=alignRight headers="br1 br4 bc1 bc7">8 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3163 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">346 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1200 </TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1617 </TD><TD class=alignRight headers="br1 br4 bc8 bc14">635 </TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">2 </TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">1 </TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">1 </TD><TD class=alignRight headers="br1 br5 bc1 bc7">6 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3446 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">319 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1206 </TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">1921 </TD><TD class=alignRight headers="br1 br5 bc8 bc14">642 </TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">3 </TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">1 </TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">2 </TD><TD class=alignRight headers="br1 br6 bc1 bc7">16 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">9542 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">133 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3638 </TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">5771 </TD><TD class=alignRight headers="br1 br6 bc8 bc14">778 </TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0 </TD><TD class=alignRight headers="br1 br7 bc1 bc7">0 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">164 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">20 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">143 </TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">1 </TD><TD class=alignRight headers="br1 br7 bc8 bc14">1 </TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">13 </TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">5 </TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">2 </TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">6 </TD><TD class=alignRight headers="br1 br8 bc1 bc7">51 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">20423 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">1109 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">7650 </TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">11664 </TD><TD class=alignRight headers="br1 br8 bc8 bc14">3768 </TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza strain characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 1299 influenza viruses. The 630 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 200 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 366 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 103 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).

Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =1299

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral resistance

During the 2012-13 season, NML has tested 1261 influenza viruses for resistance to oseltamivir, and 1222 influenza viruses for resistance to zanamivir. Among these, one A(H3N2) virus was resistant to oseltamivir and zanamivir. A total of 1224 influenza A viruses were tested for amantadine resistance and all but one were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">597</TD><TD class=alignRight headers="cr2 cc3">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc5">596</TD><TD class=alignRight headers="cr2 cc6">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc8">986</TD><TD class=alignRight headers="cr2 cc9">985 (99.9%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">201</TD><TD class=alignRight headers="cr3 cc3">0</TD><TD class=alignRight headers="cr3 cc5">197</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">238</TD><TD class=alignRight headers="cr3 cc9">238 (100%)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">463</TD><TD class=alignRight headers="cr4 cc3">0</TD><TD class=alignRight headers="cr4 cc5">429</TD><TD class=alignRight headers="cr4 cc6">0</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">1261</TD><TD class=alignRight headers="cr5 cc3">1 (0.1%)</TD><TD class=alignRight headers="cr5 cc5">1222</TD><TD class=alignRight headers="cr5 cc6">1 (0.1%)</TD><TD class=alignRight headers="cr5 cc8">1224</TD><TD class=alignRight headers="cr5 cc9">1223 (99.9%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate decreased from 15.6 ILI consultations per 1,000 patient visits in week 19 to 13.0 / 1,000 in week 20, and is within the expected range (Figure 7). In week 20, the highest consultation rate was observed in children less than 5 years of age (31.0/1,000).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)



Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

In week 20, 11 laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalizations were reported by the Immunization Monitoring Program Active (IMPACT) network, the same number as in week 19. Nine of the 11 cases reported in week 20 were identified with influenza B. The age distribution is as follows: two cases 0-5 months of age, three 6-23 months of age, three 2-4 years of age, and three 10-16 years of age. Two cases were admitted to an intensive care unit (ICU) during week 20, one child 2-4 years of age and one 10-16 years of age. No deaths were reported in week 20.

Since the start of the 2012-13 season, a total of 873 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 622 (71.2%) with influenza A [of which 120 (19.3%) were A(H3N2), 25 (4.0%) were A(H1N1)pdm09 and the remaining 477 were A(unsubtyped); and 251 (28.8%) with influenza B. The distribution of cases by age group is as follows: 161 (18.4%) <6 months of age; 202 (23.1%) age 6-23 months; 250 (28.6%) age 2-4 years; 186 (21.3%) age 5-9 years; and 74 (8.5%) age 10-16 years. Of the 873 cases, 98 (11.2%) were admitted to the ICU. Of the 73 ICU admissions with available data, 61 (83.6%) cases had at least one underlying condition. One death has been reported to date this season in a child 6-23 months of age with an underlying condition, with influenza B.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associated paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

Active surveillance of laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network concluded for the 2012-13 influenza season on April 30th, 2013. However, the PCIRN-SOS network continues to report limited data on laboratory-confirmed cases of influenza identified through passive surveillance at 16 out of 17 hospital sites. In week 20, five hospitalizations were reported: four of the five were cases of influenza B and one was influenza A(H3N2); two cases were ≥65 years of age, two were 45-64 years, and one case was <20 years of age. No ICU admissions or deaths were reported in week 20.

The cumulative data for the season to date includes data from active surveillance from November 4, 2012 to April 30, 2013 and data from passive surveillance from May 1 to 18, 2013. The cumulative number of cases was 1,798: 1,622 (90.2%) with influenza A [of which 311 were A(H3N2), 19 were A(H1N1)pdm09, and 1292 were A(unsubtyped)]; 130 (7.2%) with influenza B, and the type has not been reported for 46 cases. The age distribution of hospitalizations is as follows: 1225 (68.1%) were ≥65 years of age, 368 (20.5%) were 45-64 years, 194 (10.8%) were 20-44 years, and 11 (0.6%) were <20 years of age. ICU admission was required for 216 hospitalizations; the majority of which were adults ≥65 years of age (123; 56.9%). A total of 116 deaths have been reported: 26 with influenza A(H3N2), one with A(H1N1)pdm09, 82 with A(unsubtyped), 6 with influenza B, and one untyped. More than 85% of the deaths (99/116) were in adults ≥65 years of age, 14 (12.1%) were adults 45-64 years of age, and 3 (2.6%) were 20-44 years of age.

Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associated adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)

In week 20, 46 laboratory-confirmed influenza-associated hospitalizations were reported from participating provinces and territories*. For the second week in a row, the majority of cases were influenza B (58.7%). The highest proportion of hospitalisations were in adults ≥65 years of age (50.0%), followed by children 0-4 years of age (23.9%). Of the 15 cases with available data, two were admitted to the ICU; one adult ≥65 years of age with influenza A(H3), and the other a child 0-4 years of age with influenza B. Four deaths were reported in week 20; two children 0-4 years of age and two adults ≥65 years of age, all with influenza A.

To date this season, 4,859 influenza-associated hospitalizations have been reported, of which 87.5% have been influenza A. Of those subtyped (49.0%), influenza A(H3) was the predominant influenza strain. The cumulative proportion of influenza B among hospitalizations with influenza continues to increase (12.5% in week 20). Age information was available for 4,856 cases, and the age distribution is as follows: 2,573 (53.0%) were ≥65 years of age; 804 (16.6%) were 45-64 years of age; 437 (9.0%) were 20-44 years of age; 39 (0.8%) were 15-19 years of age; 249 (5.1%) were 5-14 years; and 754 (15.5%) were 0-4 years of age. Of the 1,365 cases with available data, there have been 218 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults 45-64 years of age, followed by adults ≥65 years of age (36.2% and 33.9%, respectively). To date, 302 deaths have been reported: 248 adults ≥65 years of age, 35 adults 45-64 years; 11 adults 20-44 years, one child 5-14 years of age, and seven children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

.../
http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Week 18

FluWatch report: May 5 to May 11, 2013 (Week 19)

Posted 2013-05-17For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w19_13/pdf/fw2013-19-eng.pdf">FluWatch report: May 5 to May 11, 2013 (Week 19) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• Influenza activity in Canada continued its slow decline in week 19, with the percentage of laboratory tests positive for influenza at 8.6%. Influenza B was the predominant strain, but detections continued to decrease.
• Detections of rhinovirus and parainfluenza continued to increase slowly, while detections of most other respiratory viruses decreased in week 19.
• The ILI consultation rate decreased slightly, but was above the expected range. Fewer regions reported localized activity compared to the previous week.

Influenza Activity (geographic spread) and Outbreaks

In week 19, five regions in Ontario reported localized activity and 28 regions reported sporadic activity. The number of regions reporting widespread or localized activity decreased compared to the previous week (Figures 1 and 2). Three new influenza outbreaks were reported: one in a long-term-care facility and two in other facilities or communities (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 19





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=58)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The overall percentage of positive influenza tests decreased slightly compared to recent weeks, from 9.8% in week 18 to 8.6% in week 19. Detections of influenza B decreased for the third consecutive week, and represented 86.5% of total positive influenza detections in week 19 (Figure 4). Among the influenza viruses detected in week 19 (n=229), 13.5% were positive for influenza A viruses [of which 41.9% were A(H1N1)pdm09, 19.4% were A(H3), and 38.7% were A(unsubtyped)] (Table 1). Cumulative influenza virus detections by type/subtype to date are as follows: 85.9% influenza A [34.4% A(H3), 4.6% A(H1N1)pdm09 and 60.9% A(unsubtyped)] and 14.1% influenza B (Table 1).
Detailed information on age and type/subtype has been received for 26,985 cases to date this season (Table 2). The proportion of cases by age group is as follows: 14.9% <5 years; 10.5% between 5-19 years; 16.4% between 20-44 years; 17.5% between 45-64 years of age; 40.7% ≥65 years.

The percentage of positive tests for rhinovirus decreased slightly from 16.5% in week 18 to 15.8% in week 19, but has been slowly increasing since week 01. The percentage of positive tests for parainfluenza (7.4%) increased, continuing its gradual increase over the past 11 weeks. The percentage of tests positive for respiratory syncytial virus (RSV) (3.1%) continued its decline from a peak in week 08. The percentage of positive tests for human metapneumovirus (hMPV) (4.2%) has been decreasing slowly since week 14. The percentage of positive tests for coronavirus (2.3%) increased in week 19 after a slow decline from week 04 to 18 (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(May 5 to May 11, 2013)
</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to May 11, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B
</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B
</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*
</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*
</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD headers="ar1 ar2 ac1 ac2 ac3">4</TD><TD headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD headers="ar1 ar2 ac1 ac2 ac5">1</TD><TD headers="ar1 ar2 ac1 ac2 ac6">1</TD><TD headers="ar1 ar2 ac1 ac2 ac7">2</TD><TD headers="ar1 ar2 ac1 ac8">11</TD><TD headers="ar1 ar2 ac9 ac10 ac11">1910</TD><TD headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD headers="ar1 ar2 ac9 ac10 ac13">1450</TD><TD headers="ar1 ar2 ac9 ac10 ac14">219</TD><TD headers="ar1 ar2 ac9 ac10 ac15">241</TD><TD headers="ar1 ar2 ac9 ac16">405</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD headers="ar1 ar3 ac1 ac2 ac3">7</TD><TD headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD headers="ar1 ar3 ac1 ac2 ac5">2</TD><TD headers="ar1 ar3 ac1 ac2 ac6">4</TD><TD headers="ar1 ar3 ac1 ac2 ac7">1</TD><TD headers="ar1 ar3 ac1 ac8">36</TD><TD headers="ar1 ar3 ac9 ac10 ac11">2354</TD><TD headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD headers="ar1 ar3 ac9 ac10 ac13">1769</TD><TD headers="ar1 ar3 ac9 ac10 ac14">441</TD><TD headers="ar1 ar3 ac9 ac10 ac15">144</TD><TD headers="ar1 ar3 ac9 ac16">786</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD headers="ar1 ar4 ac1 ac2 ac3">0</TD><TD headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD headers="ar1 ar4 ac1 ac2 ac5">0</TD><TD headers="ar1 ar4 ac1 ac2 ac6">0</TD><TD headers="ar1 ar4 ac1 ac2 ac7">0</TD><TD headers="ar1 ar4 ac1 ac8">13</TD><TD headers="ar1 ar4 ac9 ac10 ac11">836</TD><TD headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD headers="ar1 ar4 ac9 ac10 ac13">476</TD><TD headers="ar1 ar4 ac9 ac10 ac14">73</TD><TD headers="ar1 ar4 ac9 ac10 ac15">287</TD><TD headers="ar1 ar4 ac9 ac16">298</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD headers="ar1 ar5 ac1 ac2 ac3">1</TD><TD headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD headers="ar1 ar5 ac1 ac2 ac5">1</TD><TD headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD headers="ar1 ar5 ac1 ac2 ac7">0</TD><TD headers="ar1 ar5 ac1 ac8">16</TD><TD headers="ar1 ar5 ac9 ac10 ac11">658</TD><TD headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD headers="ar1 ar5 ac9 ac10 ac13">79</TD><TD headers="ar1 ar5 ac9 ac10 ac14">10</TD><TD headers="ar1 ar5 ac9 ac10 ac15">569</TD><TD headers="ar1 ar5 ac9 ac16">100</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD headers="ar1 ar6 ac1 ac2 ac3">9</TD><TD headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD headers="ar1 ar6 ac1 ac2 ac5">2</TD><TD headers="ar1 ar6 ac1 ac2 ac6">5</TD><TD headers="ar1 ar6 ac1 ac2 ac7">2</TD><TD headers="ar1 ar6 ac1 ac8">34</TD><TD headers="ar1 ar6 ac9 ac10 ac11">8257</TD><TD headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD headers="ar1 ar6 ac9 ac10 ac13">3780</TD><TD headers="ar1 ar6 ac9 ac10 ac14">374</TD><TD headers="ar1 ar6 ac9 ac10 ac15">4103</TD><TD headers="ar1 ar6 ac9 ac16">881</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>

</TH><TD headers="ar1 ar7 ac1 ac2 ac3">5</TD><TD headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD headers="ar1 ar7 ac1 ac2 ac6">1</TD><TD headers="ar1 ar7 ac1 ac2 ac7">4</TD><TD headers="ar1 ar7 ac1 ac8">77</TD><TD headers="ar1 ar7 ac9 ac10 ac11">9802</TD><TD headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD headers="ar1 ar7 ac9 ac10 ac13">546</TD><TD headers="ar1 ar7 ac9 ac10 ac14">36</TD><TD headers="ar1 ar7 ac9 ac10 ac15">9220</TD><TD headers="ar1 ar7 ac9 ac16">1846</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>

</TH><TD headers="ar1 ar8 ac1 ac2 ac3">4</TD><TD headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD headers="ar1 ar8 ac1 ac2 ac5">0</TD><TD headers="ar1 ar8 ac1 ac2 ac6">2</TD><TD headers="ar1 ar8 ac1 ac2 ac7">2</TD><TD headers="ar1 ar8 ac1 ac8">11</TD><TD headers="ar1 ar8 ac9 ac10 ac11">1863</TD><TD headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD headers="ar1 ar8 ac9 ac10 ac13">771</TD><TD headers="ar1 ar8 ac9 ac10 ac14">73</TD><TD headers="ar1 ar8 ac9 ac10 ac15">1019</TD><TD headers="ar1 ar8 ac9 ac16">71</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>

</TH><TD headers="ar1 ar9 ac1 ac2 ac3">0</TD><TD headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD headers="ar1 ar9 ac1 ac2 ac6">0</TD><TD headers="ar1 ar9 ac1 ac2 ac7">0</TD><TD headers="ar1 ar9 ac1 ac8">0</TD><TD headers="ar1 ar9 ac9 ac10 ac11">388</TD><TD headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD headers="ar1 ar9 ac9 ac10 ac13">165</TD><TD headers="ar1 ar9 ac9 ac10 ac14">8</TD><TD headers="ar1 ar9 ac9 ac10 ac15">215</TD><TD headers="ar1 ar9 ac9 ac16">7</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>

</TH><TD headers="ar1 ar10 ac1 ac2 ac3">0</TD><TD headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD headers="ar1 ar10 ac1 ac2 ac5">0</TD><TD headers="ar1 ar10 ac1 ac2 ac6">0</TD><TD headers="ar1 ar10 ac1 ac2 ac7">0</TD><TD headers="ar1 ar10 ac1 ac8">0</TD><TD headers="ar1 ar10 ac9 ac10 ac11">116</TD><TD headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD headers="ar1 ar10 ac9 ac10 ac13">76</TD><TD headers="ar1 ar10 ac9 ac10 ac14">9</TD><TD headers="ar1 ar10 ac9 ac10 ac15">31</TD><TD headers="ar1 ar10 ac9 ac16">1</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>

</TH><TD headers="ar1 ar11 ac1 ac2 ac3">1</TD><TD headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD headers="ar1 ar11 ac1 ac2 ac7">1</TD><TD headers="ar1 ar11 ac1 ac8">0</TD><TD headers="ar1 ar11 ac9 ac10 ac11">718</TD><TD headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD headers="ar1 ar11 ac9 ac10 ac13">152</TD><TD headers="ar1 ar11 ac9 ac10 ac14">0</TD><TD headers="ar1 ar11 ac9 ac10 ac15">566</TD><TD headers="ar1 ar11 ac9 ac16">16</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD headers="ar1 ar12 ac1 ac2 ac3">31</TD><TD headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD headers="ar1 ar12 ac1 ac2 ac5">6</TD><TD headers="ar1 ar12 ac1 ac2 ac6">13</TD><TD headers="ar1 ar12 ac1 ac2 ac7">12</TD><TD headers="ar1 ar12 ac1 ac8">198</TD><TD headers="ar1 ar12 ac9 ac10 ac11">26902</TD><TD headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD headers="ar1 ar12 ac9 ac10 ac13">9264</TD><TD headers="ar1 ar12 ac9 ac10 ac14">1243</TD><TD headers="ar1 ar12 ac9 ac10 ac15">16395</TD><TD headers="ar1 ar12 ac9 ac16">4411</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(May 5 to May 11, 2013)
</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to May 11, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively. </TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">2</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">1</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">1</TD><TD class=alignRight headers="br1 br2 bc1 bc7">24</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">3127</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">333</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">1166</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1628</TD><TD class=alignRight headers="br1 br2 bc8 bc14">901</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">1</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br3 bc1 bc7">21</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1687</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">95</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">825</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">767</TD><TD class=alignRight headers="br1 br3 bc8 bc14">1142</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">4</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">3</TD><TD class=alignRight headers="br1 br4 bc1 bc7">19</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3661</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">478</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1539</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1644</TD><TD class=alignRight headers="br1 br4 bc8 bc14">764</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">2</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">1</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br5 bc1 bc7">23</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3956</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">443</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1563</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">1950</TD><TD class=alignRight headers="br1 br5 bc8 bc14">754</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">4</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">4</TD><TD class=alignRight headers="br1 br6 bc1 bc7">26</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">10140</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">163</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">4165</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">5812</TD><TD class=alignRight headers="br1 br6 bc8 bc14">853</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br7 bc1 bc7">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">164</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">20</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">143</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">1</TD><TD class=alignRight headers="br1 br7 bc8 bc14">1</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">13</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">3</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">2</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">8</TD><TD class=alignRight headers="br1 br8 bc1 bc7">113</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">22735</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">1532</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">9401</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">11802</TD><TD class=alignRight headers="br1 br8 bc8 bc14">4415</TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza strain characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 1251 influenza viruses. The 603 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 194 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 356 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 98 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =1251

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral resistance

During the 2012-13 season, NML has tested 1223 influenza viruses for resistance to oseltamivir, and 1221 influenza viruses for resistance to zanamivir. Among these, one A(H3N2) virus was resistant to oseltamivir and zanamivir. A total of 1210 influenza A viruses were tested for amantadine resistance and all but one were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">595</TD><TD class=alignRight headers="cr2 cc3">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc5">596</TD><TD class=alignRight headers="cr2 cc6">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc8">980</TD><TD class=alignRight headers="cr2 cc9">979 (99.9%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">199</TD><TD class=alignRight headers="cr3 cc3">0</TD><TD class=alignRight headers="cr3 cc5">196</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">230</TD><TD class=alignRight headers="cr3 cc9">230 (100%)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">429</TD><TD class=alignRight headers="cr4 cc3">0</TD><TD class=alignRight headers="cr4 cc5">429</TD><TD class=alignRight headers="cr4 cc6">0</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">1223</TD><TD class=alignRight headers="cr5 cc3">1 (0.1%)</TD><TD class=alignRight headers="cr5 cc5">1221</TD><TD class=alignRight headers="cr5 cc6">1 (0.1%)</TD><TD class=alignRight headers="cr5 cc8">1210</TD><TD class=alignRight headers="cr5 cc9">1209 (99.9%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate decreased from 18.3 ILI consultations per 1,000 patient visits in week 18 to 16.1 / 1,000 in week 19, and is above the expected range (Figure 7). In week 19, the highest consultation rate was observed in children 5-19 years of age (33.1/1,000).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)



Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

In week 19, 11 laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalizations were reported by the Immunization Monitoring Program Active (IMPACT) network, compared to 16 in week 18. All of the cases reported in week 19 were identified with influenza B. The age distribution is as follows: two cases 0-5 months of age, two 6-23 months of age, four 2-4 years of age, and three 5-9 years of age. Four cases were admitted to an intensive care unit (ICU) during week 19, one child 0-5 months of age, one 6-23 months of age, one 2-4 years of age and one 5-9 years of age; all with influenza B. No deaths were reported in week 19.

Since the start of the 2012-13 season, a total of 863 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 621 (72.0%) with influenza A [of which 120 (19.3%) were A(H3N2), 25 (4.0%) were A(H1N1)pdm09 and the remaining 476 were A(unsubtyped); and 242 (28.0%) with influenza B. The distribution of cases by age group is as follows: 159 (18.4%) <6 months of age; 200 (23.2%) age 6-23 months; 247 (28.6%) age 2-4 years; 186 (21.6%) age 5-9 years; and 71 (8.2%) age 10-16 years. Of the 863 cases, 94 (10.9%) were admitted to the ICU. Of the 72 ICU admissions with available data, 62 (86.1%) cases had at least one underlying condition. One death has been reported to date this season in a child 6-23 months of age with an underlying condition, with influenza B.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associate paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

Active surveillance of laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network has concluded for the 2012-13 influenza season. However, the PCIRN-SOS network will continue to report limited data on laboratory-confirmed cases of influenza. In week 19, 13 hospitalizations were reported from 14 of the 17 PCIRN sites: 12 were cases of influenza B and one case of influenza A. Nine cases were ≥65 years of age, one was 45-64 years, and one was <20 years of age. One ICU admission and no deaths were reported in week 19.

Cumulative data for the season to date includes data from active surveillance from November 4, 2012 to April 30, 2013 and data from passive surveillance since May 1, 2013. The cumulative number of cases reported by the PCIRN-SOS network was 1,792 influenza-associated adult hospitalizations: 90.5% with influenza A [of which 310 were A(H3N2), 19 were A(H1N1)pdm09, and 1292 were A(unsubtyped)]; 125 with influenza B, and the type has not been reported for 46 cases. The age distribution of hospitalizations is as follows: 1221 (68.1%) were ≥65 years of age, 365 (20.4%) were 45-64 years, 194 (10.8%) were 20-44 years, and 10 (0.6%) were <20 years of age. ICU admission was required for 215 hospitalizations; the majority of which were adults ≥65 years of age (125; 58.1%). 115 deaths have been reported: 26 with influenza A(H3N2), one with A(H1N1)pdm09, 82 with A(unsubtyped), 5 with influenza B, and one untyped. More than 85% of the deaths (98/115) were in adults ≥65 years of age, 12.2 (14%) were adults 45-64 years of age, and 3 (2.6%) were 20-44 years of age.

Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associate adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)

In week 19, 44 laboratory-confirmed influenza-associated hospitalizations were reported from participating provinces and territories<SUP>*</SUP>. For the first time during the 2012-13 season, the majority of cases were influenza B (77.3%). The highest proportion of hospitalisations were in adults ≥65 years of age (40.9%), followed by children 0-4 years of age (22.7%). Of the 21 cases with available data, three cases were admitted to the ICU, all with influenza A(unsubtyped); two were ≥65 years of age and one was 45-64 years of age. One death was reported in week 19, an adult ≥65 years of age with influenza B.

To date this season, 4,763 influenza-associated hospitalizations have been reported, of which 88.7% have been influenza A. Of those subtyped (48.9%), influenza A(H3) was the predominant influenza strain. The cumulative proportion of hospitalizations with influenza B continues to increase (11.3% in week 19). Age information was available for 4,760 cases, and the age distribution is as follows: 2,529 (53.1%) were ≥65 years of age; 794 (16.7%) were 45-64 years of age; 429 (9.0%) were 20-44 years of age; 40 (0.8%) were 15-19 years of age; 230 (4.8%) were 5-14 years; and 738 (15.5%) were 0-4 years of age. Of the 1,300 cases with available data, there have been 213 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults 45-64 years of age, followed by adults ≥65 years of age (35.4% and 34.4%, respectively). To date, 298 deaths have been reported: 246 adults ≥65 years of age, 35 adults 45-64 years; 11 adults 20-44 years, one child 5-14 years of age, and 5 children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

.../
http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Week 18

FluWatch report: April 28 to May 4, 2013 (Week 18)

Posted 2013-05-10For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w18_13/pdf/fw2013-18-eng.pdf">FluWatch report: April 28 to May 4, 2013 (Week 18) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• Influenza activity in Canada continued its slow decline in week 18, with the percentage of laboratory tests positive for influenza at 10%. Influenza B was the predominant strain, but detections continued to decrease.
• Detections of rhinovirus continued to increase, while detections of other respiratory viruses were stable or decreasing in week 18.
• The ILI consultation rate increased slightly and was above the expected range. However, fewer regions reported localized activity compared to the previous week.

Influenza Activity (geographic spread) and Outbreaks

In week 18, seven regions [AB(1), ON(4), QC(1) and NB(1)] reported localized activity and 25 regions reported sporadic activity. The number of regions reporting widespread or localized activity decreased compared to the previous week (Figures 1 and 2). Six new influenza outbreaks were reported: five in long-term-care facilities and one in a school (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 18





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=58)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The overall percentage of positive influenza tests decreased slightly compared to recent weeks, from 11.2 in week 17 to 10.0% in week 18. Detections of influenza B decreased for the second consecutive week, and represented 86.4% of total positive influenza detections in week 18 (Figure 4). Among the influenza viruses detected in week 18 (n=301), 13.6% were positive for influenza A viruses [of which 48.8% were A(H1N1)pdm09, 9.8% were A(H3), and 41.5% were A(unsubtyped)] (Table 1). Cumulative influenza virus detections by type/subtype to date are as follows: 86.5% influenza A [34.5% A(H3), 4.6% A(H1N1)pdm09 and 61.0% A(unsubtyped)] and 13.5% influenza B (Table 1).
Detailed information on age and type/subtype has been received for 23,888 cases to date this season (Table 2). The proportion of cases by age group is as follows: 14.1% <5 years; 9.9% between 5-19 years; 15.7% between 20-44 years; 17.0% between 45-64 years of age; 43.2% ≥65 years.
The percentage of positive tests for rhinovirus increased from 12.5% in week 17 to 14.1% in week 18, and has been slowly increasing since week 01. The percentage of positive tests for parainfluenza (5.4%) was stable since week 16, but has been increasing gradually over the past 10 weeks. The percentage of tests positive for respiratory syncytial virus (RSV) (4.5%) continued its decline from a peak in week 08. The percentage of positive tests for human metapneumovirus (hMPV) (5.0%) has been stable since week 16, and the percentage of positive tests for coronavirus (0.8%) has been decreasing slowly since week 04 (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(April 28 to May 4, 2013)
</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to May 4, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B
</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B
</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*
</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*
</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">3</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">1</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">2</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">11</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1907</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1450</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">218</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">239</TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">397</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">7</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">2</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">4</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">40</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2347</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1766</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">437</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">144</TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">748</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">27</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">836</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">476</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">73</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">287</TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">285</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">2</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">657</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">78</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">569</TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">84</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">7</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">1</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">4</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">57</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8248</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3778</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">369</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4101</TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">843</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>

</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">12</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">2</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">10</TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">109</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9797</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">35</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9216</TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1768</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>

</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">6</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">6</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">13</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1859</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">771</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">71</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1017</TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">60</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>

</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">1</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">388</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">8</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">215</TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">7</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>

</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">2</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">116</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">76</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">9</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">31</TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>

</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">717</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">152</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">565</TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">16</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">41</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">4</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">20</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">17</TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">260</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">26872</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9258</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1230</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16384</TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">4209</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(April 28 to May 4, 2013)
</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to May 4, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively. </TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight>5</TD><TD class=alignRight>2</TD><TD class=alignRight>0</TD><TD class=alignRight>3</TD><TD class=alignRight>32</TD><TD class=alignRight>2674</TD><TD class=alignRight>214</TD><TD class=alignRight>861</TD><TD class=alignRight>1599</TD><TD class=alignRight>706</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight>0</TD><TD class=alignRight>0</TD><TD class=alignRight>0</TD><TD class=alignRight>0</TD><TD class=alignRight>34</TD><TD class=alignRight>1455</TD><TD class=alignRight>66</TD><TD class=alignRight>639</TD><TD class=alignRight>750</TD><TD class=alignRight>908</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight>4</TD><TD class=alignRight>1</TD><TD class=alignRight>0</TD><TD class=alignRight>3</TD><TD class=alignRight>23</TD><TD class=alignRight>3170</TD><TD class=alignRight>339</TD><TD class=alignRight>1217</TD><TD class=alignRight>1614</TD><TD class=alignRight>586</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight>4</TD><TD class=alignRight>2</TD><TD class=alignRight>0</TD><TD class=alignRight>2</TD><TD class=alignRight>27</TD><TD class=alignRight>3463</TD><TD class=alignRight>312</TD><TD class=alignRight>1233</TD><TD class=alignRight>1918</TD><TD class=alignRight>597</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight>2</TD><TD class=alignRight>0</TD><TD class=alignRight>0</TD><TD class=alignRight>2</TD><TD class=alignRight>45</TD><TD class=alignRight>9611</TD><TD class=alignRight>132</TD><TD class=alignRight>3713</TD><TD class=alignRight>5766</TD><TD class=alignRight>718</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight>0</TD><TD class=alignRight>0</TD><TD class=alignRight>0</TD><TD class=alignRight>0</TD><TD class=alignRight>0</TD><TD class=alignRight>166</TD><TD class=alignRight>20</TD><TD class=alignRight>144</TD><TD class=alignRight>2</TD><TD class=alignRight>1</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight>15</TD><TD class=alignRight>5</TD><TD class=alignRight>0</TD><TD class=alignRight>10</TD><TD class=alignRight>161</TD><TD class=alignRight>20539</TD><TD class=alignRight>1083</TD><TD class=alignRight>7807</TD><TD class=alignRight>11649</TD><TD class=alignRight>3516</TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza strain characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 1221 influenza viruses. The 600 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 193 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 338 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 90 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =1221

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral resistance

During the 2012-13 season, NML has tested 1149 influenza viruses for resistance to oseltamivir, and 1145 influenza viruses for resistance to zanamivir. Among these, one A(H3N2) virus was resistant to oseltamivir and zanamivir. A total of 1180 influenza A viruses were tested for amantadine resistance and all but one were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">572</TD><TD class=alignRight headers="cr2 cc3">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc5">573</TD><TD class=alignRight headers="cr2 cc6">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc8">955</TD><TD class=alignRight headers="cr2 cc9">954 (99.9%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">194</TD><TD class=alignRight headers="cr3 cc3">0</TD><TD class=alignRight headers="cr3 cc5">190</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">225</TD><TD class=alignRight headers="cr3 cc9">225 (100%)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">383</TD><TD class=alignRight headers="cr4 cc3">0</TD><TD class=alignRight headers="cr4 cc5">382</TD><TD class=alignRight headers="cr4 cc6">0</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">1149</TD><TD class=alignRight headers="cr5 cc3">1 (0.1%)</TD><TD class=alignRight headers="cr5 cc5">1145</TD><TD class=alignRight headers="cr5 cc6">1 (0.1%)</TD><TD class=alignRight headers="cr5 cc8">1180</TD><TD class=alignRight headers="cr5 cc9">1179 (99.9%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate increased from 14.5 ILI consultations per 1,000 patient visits in week 17 to 17.6 / 1,000 in week 18, and is above the expected range (Figure 7). In week 18, the highest consultation rate was observed in children under 5 years of age (63.2/1,000).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)



Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

In week 18, 16 laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalizations were reported by the Immunization Monitoring Program Active (IMPACT) network, compared to 15 in week 17. All of the cases reported in week 18 were identified with influenza B. The age distribution is as follows: 3 (18.8%) between 0-5 months, 2 (12.5%) between 6-23 months, 4 (25.0%) 2-4 years of age, and 7 (43.8%) 5-9 years of age. Two cases were admitted to an intensive care unit (ICU) during week 18, one child 2-4 years of age and one 5-9 years of age; both with influenza B. No deaths were reported in week 18.
Since the start of the 2012-13 season, a total of 855 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 621 (72.6%) with influenza A [of which 120 (19.3%) were A(H3N2), 25 (4.0%) were A(H1N1)pdm09 and the remaining 476 were A(unsubtyped); and 234 (27.4%) with influenza B. The distribution of cases by age group is as follows: 157 (18.4%) <6 months of age; 199 (23.3%) age 6-23 months; 244 (28.5%) age 2-4 years; 183 (21.4%) age 5-9 years; and 72 (8.4%) age 10-16 years. Ninety-two (10.8%) of the 855 cases were admitted to the ICU. Of the 70 ICU admissions with available data, 60 (85.7%) cases had at least one co-morbidity. One death has been reported to date this season in a child 6-23 months of age with an underlying condition, with influenza B.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associate paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

PCIRN-SOS surveillance has concluded for the 2012-13 influenza season. In week 18, eight laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations were reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network. All eight hospitalizations were cases of influenza B; three cases were ≥65 years of age, two were 45-64 years, two were 20-44 years and one was <20 years of age. Two ICU admissions were reported, both cases with influenza B; one ≥65 years of age and one 45-64 years of age. No deaths were reported in week 18. Only nine of the 17 PCIRN centres reported data in week 18. A summary of final data will be included in the 2012-13 FluWatch annual report.

From November 4, 2012 to May 4, 2013, 1,779 influenza-associated adult hospitalizations were reported by the PCIRN-SOS network: 1,620 (91.1%) with influenza A [of which 310 were A(H3N2), 19 were A(H1N1)pdm09, and 1,291 were A(unsubtyped)]; 113 (6.4%) with influenza B, and the type has not been reported for 46 cases. The age distribution of hospitalizations is as follows: 1,212 (68.1%) were ≥65 years of age, 364 (20.5%) were 45-64 years, 194 (10.9%) were 20-44 years, and 9 (0.5%) were <20 years of age. ICU admission was required for 214 hospitalizations; the majority of which were adults ≥65 years of age (124; 57.9%). Of the ICU admissions, 90 (42.1%) had at least one co-morbidity, five (2.3%) had no co-morbidities, and 119 had no information to date. A total of 115 deaths have been reported: 26 with influenza A(H3N2), one with A(H1N1)pdm09, 82 with A(unsubtyped), five with influenza B, and one untyped. More than 85% of the deaths (98/115) were in adults ≥65 years of age, 14 (12.2%) were adults 45-64 years of age, and 3 (2.6%) were 20-44 years of age. Fifty-two (45.2%) deaths occurred in individuals who had at least one co-morbidity. Detailed clinical information on co-morbidities is not known for the remaining cases.

Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associate adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)

In week 18, 69 laboratory-confirmed influenza-associated hospitalizations were reported from participating provinces and territories<SUP>*</SUP>. The majority of cases were influenza A (56.5%). The highest proportion of hospitalisations were in adults ≥65 years of age (40.6%), followed by children 0-4 years of age (21.7%). Of the 17 cases with available data, six cases were admitted to the ICU, three with influenza A(H1N1)pdm09 and three with influenza B; four were ≥65 years of age, one was 45-64 years of age, and one was 5-14 years of age. Two deaths were reported in week 18, both adults ≥65 years of age with influenza A.

To date this season, 4,733 influenza-associated hospitalizations have been reported, of which 89.1% have been influenza A. Of those subtyped (48.8%), influenza A(H3) was the predominant influenza strain. The cumulative proportion of hospitalizations with influenza B continues to increase (10.9% in week 18). Age information was available for 4,730 cases, and the age distribution is as follows: 2,518 (53.2%) were ≥65 years of age; 789 (16.7%) were 45-64 years of age; 429 (9.1%) were 20-44 years of age; 40 (0.8%) were 15-19 years of age; 228 (4.8%) were 5-14 years; and 726 (15.3%) were 0-4 years of age. Of the 1,293 cases with available data, there have been 204 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults 45-64 years of age, followed by adults ≥65 years of age (35.8% and 34.3%, respectively). To date, 297 deaths have been reported: 245 adults ≥65 years of age, 35 adults 45-64 years; 11 adults 20-44 years, one child 5-14 years of age, and 5 were children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.


.../
http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Week 17

FluWatch report: April 21 to April 27, 2013 (Week 17)

Posted 2013-05-03For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w17_13/pdf/fw2013-17-eng.pdf">FluWatch report: April 21 to April 27, 2013 (Week 17) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• Influenza activity in Canada continued its slow decline in week 17, with the percentage of laboratory tests positive for influenza at 11%. Detections of influenza B decreased to 81.7% of positive specimens in week 17.
• The ILI consultation rate decreased slightly, and the number of regions reporting localized activity was the same as the previous week.
• The increased circulation of influenza B in recent weeks has been reflected in both adult and paediatric hospitalizations. Overall this season, 20-26% of paediatric hospitalizations have been associated with influenza B compared to 7% of adult hospitalizations.
• Detections of rhinovirus and parainfluenza were both stable in week 17, but have been increasing gradually in recent weeks. RSV continued the downward trend observed since week 08.

Influenza Activity (geographic spread) and Outbreaks

In week 17, no regions reported widespread activity, twelve regions [AB(1), SK(1), MB(1), ON(6), QC(2) and NT(1)] reported localized activity and 24 regions reported sporadic activity. The number of regions reporting widespread or localized activity was the same as the previous week (Figures 1 and 2). Eight new influenza outbreaks were reported: four in long-term-care facilities, two in hospitals, and two in schools (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 17





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=56)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The overall percentage of positive influenza tests decreased slightly compared to recent weeks, from an average of 11.7% during weeks 11 to 16, to 11.0% in week 17. Detections of influenza B decreased for the second consecutive week, to 81.7% of positive influenza detections in week 17 (Figure 4). Among the influenza viruses detected in week 17 (n=371), 18.3% were positive for influenza A viruses [of which 45.6% were A(H1N1)pdm09, 16.2% were A(H3), and 38.2% were A(unsubtyped)] (Table 1). Cumulative influenza virus detections by type/subtype to date are as follows: 87.2% influenza A [34.5% A(H3), 4.5% A(H1N1)pdm09 and 61.0% A(unsubtyped)] and 12.8% influenza B (Table 1).
Detailed information on age and type/subtype has been received for 23,646 cases to date this season (Table 2). The proportion of cases by age group is as follows: 14.1% <5 years; 9.8% between 5-19 years; 15.7% between 20-44 years; 17.0% between 45-64 years of age; 43.4% ≥65 years.

The percentage of positive tests for rhinovirus was similar to the previous week at 11.6% in week 17, but has been slowly increasing since week 01. The percentage of positive tests for parainfluenza (5.2%) has also been increasing gradually over the past 10 weeks. The percentage of tests positive for respiratory syncytial virus (RSV) (6.1%) continued its decline from a peak in week 08. The percentage of positive tests for human metapneumovirus (hMPV) (4.7%) decreased for the third week in a row, and the percentage of positive tests for coronavirus (1.6%) has been decreasing slowly since week 04 (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(April 21 to April 27, 2013)
</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to April 27, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B
</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B
</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*
</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*
</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">8</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">1</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">6</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">9</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1909</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1448</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">220</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">241</TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">373</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">13</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">4</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">9</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">54</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2340</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1764</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">433</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">143</TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">706</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">3</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">1</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">21</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">834</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">476</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">73</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">285</TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">258</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">12</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">657</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">78</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">569</TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">82</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">21</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">5</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">12</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">4</TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">64</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8241</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3776</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">365</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4100</TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">788</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>

</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">11</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">1</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">10</TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">132</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9785</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">33</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9206</TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1659</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>

</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">10</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1853</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">771</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">65</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1017</TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">47</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>

</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">6</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">1</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">5</TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">388</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">8</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">215</TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">6</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>

</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">3</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">2</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">114</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">76</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">7</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">31</TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>

</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">1</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">1</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">715</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">152</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">563</TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">16</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">68</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">11</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">31</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">26</TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">303</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">26836</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9252</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1214</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16370</TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">3936</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(April 21 to April 27, 2013)
</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to April 27, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively. </TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">8</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">1</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">6</TD><TD class=alignRight headers="br1 br2 bc1 bc7">32</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">2668</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">212</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">860</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1596</TD><TD class=alignRight headers="br1 br2 bc8 bc14">667</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br3 bc1 bc7">48</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1452</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">66</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">638</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">748</TD><TD class=alignRight headers="br1 br3 bc8 bc14">860</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">7</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">6</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">1</TD><TD class=alignRight headers="br1 br4 bc1 bc7">23</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3163</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">335</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1217</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1611</TD><TD class=alignRight headers="br1 br4 bc8 bc14">548</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">7</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">4</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">3</TD><TD class=alignRight headers="br1 br5 bc1 bc7">39</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3454</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">308</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1231</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">1915</TD><TD class=alignRight headers="br1 br5 bc8 bc14">561</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">11</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">4</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">4</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">3</TD><TD class=alignRight headers="br1 br6 bc1 bc7">51</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">9604</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">130</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3711</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">5763</TD><TD class=alignRight headers="br1 br6 bc8 bc14">669</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br7 bc1 bc7">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">166</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">20</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">144</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">2</TD><TD class=alignRight headers="br1 br7 bc8 bc14">1</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">33</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">15</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">5</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">13</TD><TD class=alignRight headers="br1 br8 bc1 bc7">193</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">20507</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">1071</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">7801</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">11635</TD><TD class=alignRight headers="br1 br8 bc8 bc14">3306</TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza strain characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 1145 influenza viruses. The 565 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 189 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 313 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 78 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =1145

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral resistance

During the 2012-13 season, NML has tested 1081 influenza viruses for resistance to oseltamivir, and 1078 influenza viruses for resistance to zanamivir. Among these, one A(H3N2) virus was resistant to oseltamivir and zanamivir. A total of 1172 influenza A viruses were tested for amantadine resistance and all but one were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">559</TD><TD class=alignRight headers="cr2 cc3">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc5">559</TD><TD class=alignRight headers="cr2 cc6">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc8">952</TD><TD class=alignRight headers="cr2 cc9">951 (99.9%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">186</TD><TD class=alignRight headers="cr3 cc3">0</TD><TD class=alignRight headers="cr3 cc5">183</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">220</TD><TD class=alignRight headers="cr3 cc9">220 (100%)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">336</TD><TD class=alignRight headers="cr4 cc3">0</TD><TD class=alignRight headers="cr4 cc5">336</TD><TD class=alignRight headers="cr4 cc6">0</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">1081</TD><TD class=alignRight headers="cr5 cc3">0</TD><TD class=alignRight headers="cr5 cc5">1078</TD><TD class=alignRight headers="cr5 cc6">1 (0.1%)</TD><TD class=alignRight headers="cr5 cc8">1172</TD><TD class=alignRight headers="cr5 cc9">1171 (99.9%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate decreased slightly from 16.1 ILI consultations per 1,000 patient visits in week 16 to 15.2 / 1,000 in week 17; and remains within the expected range (Figure 7). In week 17, the highest consultation rate was observed in children under 5 years of age (33.2/1,000).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)



Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

In week 17, 15 laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalizations were reported by the Immunization Monitoring Program Active (IMPACT) network, compared to 22 in week 16. Twelve of the cases reported in week 17 were identified with influenza B. The age distribution is as follows: 3 (20.0%) between 0-5 months, 2 (13.3%) between 6-23 months, 5 (33.3%) 2-4 years of age, 3 (20.0%) 5-9 years of age and 2 (13.3%) 10-16 years of age. Two cases were admitted to an intensive care unit (ICU) during week 17, one child 6-23 months of age with A(H1N1)pdm09, and one 10-16 years of age with influenza B. No deaths were reported in week 17.

Since the start of the 2012-13 season, a total of 839 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 621 (74.0%) with influenza A [of which 121 (19.5%) were A(H3N2), 23 (3.7%) were A(H1N1)pdm09 and the remaining 477 were A(unsubtyped); and 218 (26.0%) with influenza B. The distribution of cases by age group is as follows: 154 (18.4%) <6 months of age; 198 (23.6%) age 6-23 months; 240 (28.6%) age 2-4 years; 175 (20.9%) age 5-9 years; and 72 (8.6%) age 10-16 years. Eighty-nine (10.6%) of the 839 cases were admitted to the ICU. Of the 65 ICU admissions with available data, 57 (87.7%) cases had at least one co-morbidity. One death has been reported to date this season in a child 6-23 months of age with an underlying condition, infected with influenza B.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associate paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

In week 17, four laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations were reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network, compared to 11 in week 16. Three of the four hospitalizations were cases of influenza B, and one was A(H1N1)pdm09. Two cases were ≥65 years of age, and two were 45-64 years of age. No ICU admissions or deaths were reported in week 17.

From November 4, 2012 to April 27, 2013, 1,771 influenza-associated adult hospitalizations were reported by the PCIRN-SOS network: 1,620 (91.5%) with influenza A [of which 310 were A(H3N2), 19 were A(H1N1)pdm09, and 1,291 were A(unsubtyped)]; 105 (5.9%) with influenza B, and the type has not been reported for 46 cases. The age distribution of hospitalizations is as follows: 1,209 (68.3%) were ≥65 years of age, 362 (20.4%) were 45-64 years, 192 (10.8%) were 20-44 years, and 8 (0.5%) were <20 years of age. ICU admission was required for 212 hospitalizations; the majority of which were adults ≥65 years of age (123; 58.0%). Of the ICU admissions, 90 (42.5%) had at least one co-morbidity, five (2.4%) had no co-morbidities, and 117 had no information to date. A total of 115 deaths have been reported: 26 with influenza A(H3N2), one with A(H1N1)pdm09, 82 with A(unsubtyped), five with influenza B, and one untyped. More than 85% of the deaths (98/115) were in adults ≥65 years of age, 14 (12.2%) were adults 45-64 years of age, and 3 (2.6%) were 20-44 years of age. Fifty-two (45.2%) deaths occurred in individuals who had at least one co-morbidity. Detailed clinical information on co-morbidities is not known for the remaining cases.

Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associate adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)

In week 17, 129 laboratory-confirmed influenza-associated hospitalizations were reported from participating provinces and territories<SUP>*</SUP>. The majority of cases were influenza A (63.6%). The highest proportion of hospitalisations were in adults ≥65 years of age (37.2%), followed by children 0-4 years of age (26.4%). Of the 30 cases with available data, four cases were admitted to the ICU, all with influenza A: two 45-64 years of age, one 20-44 years of age and one 0-4 years of age. Nine deaths were reported in week 17: five adults ≥65 years of age with influenza A; two adults ≥65 years of age and two 45-64 years of age with influenza B.

To date this season, 4,639 influenza-associated hospitalizations have been reported, of which 89.8% have been influenza A. Of those subtyped (47.4%), influenza A(H3) was the predominant influenza strain. The cumulative proportion of hospitalizations with influenza B continues to increase (10.2% in week 17). Age information was available for 4,636 cases, and the age distribution is as follows: 2,484 (53.6%) were ≥65 years of age; 774 (16.7%) were 45-64 years of age; 420 (9.1%) were 20-44 years of age; 40 (0.9%) were 15-19 years of age; 218 (4.7%) were 5-14 years; and 700 (15.1%) were 0-4 years of age. Of the 1,251 cases with available data, there have been 196 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults 45-64 years of age, followed by adults ≥65 years of age (36.2% and 33.7%, respectively). To date, 295 deaths have been reported: 243 adults ≥65 years of age, 35 adults 45-64 years; 11 adults 20-44 years, one child 5-14 years of age, and 5 were children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

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International Influenza Update


WHO : No new influenza surveillance update was available from the WHO since the report dated 26 April 2013.

• World Health Organization influenza update

United States : No new influenza surveillance update was available from the CDC since the report for week 16.

• Centers for Disease Control and Prevention seasonal influenza report

Europe: In week 17, most countries reported low intensity of ILI/ARI activity and a decreasing trend. In the 4 countries reporting results of 20 or more sentinel specimens, a median of 11% were positive for influenza in week 17. The proportion of influenza B detections has increased from 24% in week 03 to 62% in week 17. Among influenza A viruses in week 17, 71% were A(H3N2) and 29% were A(H1N1)pdm09. Since the beginning of the season, 63% of detections from sentinel and non-sentinel sources were influenza A [67% A(H1N1)pdm09 and 33% A(H3N2)] and 37% were influenza B. Among the 695 A(H1N1)pdm09 viruses tested for resistance to oseltamivir from 12 countries, 13 (2%) were found to contain the H275Y mutation. The number of hospitalizations for severe acute respiratory illness (SARI) and the number positive for influenza have returned to pre-season levels in most participating countries. Analysis from 12 countries revealed a broad peak of excess all-cause mortality among adults ≥65 years of age. Excess mortality was observed starting in week 01 to a peak in week 10; it has been declining since but is not yet at normal levels. In countries reporting detections of RSV, the proportion of positive tests has been declining since a peak in week 52.

• EuroFlu weekly electronic bulletin

Emerging Respiratory Pathogens


Influenza A(H7N9): Between April 27 and May 2, the WHO reported an additional 16 cases of avian influenza A(H7N9) in eastern China. Avian influenza A(H7N9) has been reported in three new provinces: Fujian, Jiangxi and Hunan. The public health risk posed by avian influenza A(H7N9) from China to Canada remains low at this time. Since March 2013, 128 cases and 26 deaths of avian influenza A(H7N9) have been reported from eight provinces and two municipalities. The number of cases (and deaths) by jurisdiction is as follows: Anhui 4 (1), Fujian 3 (0), Henan 4 (0), Hunan 3 (0), Jiangsu 26 (5), Jiangxi 4 (0), Shandong 2 (0), Zhejiang 46 (6), Beijing 1 (0), Shanghai 34 (12) and Taiwan 1(0). The location of the two most recently reported deaths have not yet been identified. More than 1,800 close contacts of confirmed cases are being closely monitored. Some of the confirmed cases had contact with animals or with an animal environment. Investigations into the source and route of transmission are still in progress, but there has been no evidence of ongoing human-to-human transmission. The WHO is in contact with national authorities and is following the event closely.

• PHAC – H7N9 avian influenza
• PHAC – A(H7N9) risk assessment
• WHO Influenza at the human-animal interface
• WHO Disease Outbreak News
• WHO Frequently Asked Questions on human infection with influenza A(H7N9)

Human Swine Influenza

No new human cases of infection with swine influenza viruses or variants were reported in week 16.

• Centers for Disease Control and Prevention seasonal influenza report

Novel Coronavirus (HCoV-EMC/2012)

Since 26 March 2013, seven new cases of novel coronavirus (HCoV-EMC/2012) from Saudi Arabia have been reported by the WHO. Five of the cases resulted in death, and two are currently in critical condition. Details have not yet been made available, however preliminary investigation show no indication of recent travel or animal contact of any of the confirmed cases. The confirmed cases are not from the same family. Since April 2012, 24 cases of laboratory-confirmed HCoV-EMC/2012 have been identified, including 16 deaths.

• PHAC – Novel coronavirus (HCoV-EMC/2012)
• PHAC – HCoV-EMC/2012 risk assessment
• WHO – Coronavirus infections

.../
http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Week 16

FluWatch report: April 14 to April 20, 2013 (Week 16)

Posted 2013-04-26For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w16_13/pdf/fw2013-16-eng.pdf">FluWatch report: April 14 to April 20, 2013 (Week 16) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• The percentage of laboratory tests positive for influenza has been stable at approximately 12% over the past six weeks. Detections of influenza B continued to increase, with influenza B detected in 89.4% of positive specimens in week 16.
• The ILI consultation rate was stable, and the number of regions reporting localized activity increased compared to the previous week, both likely due to the continued circulation of influenza B.
• Detections of rhinovirus and parainfluenza continued to increase slowly while detections of other respiratory viruses were stable or decreasing.

Influenza Activity (geographic spread) and Outbreaks

In week 16, no regions reported widespread activity, twelve regions [BC(2), AB(1), ON(5), QC(2) and NS (2)] reported localized activity and 23 regions reported sporadic activity. The number of regions reporting widespread or localized activity increased compared to the previous week (Figures 1 and 2). Ten new influenza outbreaks were reported: nine in long-term-care facilities, and one in a school (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 16





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=56)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The overall percentage of positive influenza tests was stable for the sixth consecutive week (11.3% in week 16) as a result of the continued upward trend of influenza B detections observed since week 03. Detections of influenza B increased to 89.4% of positive influenza detections in week 16 (Figure 4). Among the influenza viruses detected in week 16 (n=397), 10.6% were positive for influenza A viruses [of which 38.1% were A(H1N1)pdm09, 9.5% were A(H3), and 52.4% were A(unsubtyped)] (Table 1). Detections of influenza B increased to 81.1% of positive influenza detections in week 15, continuing the upward trend observed since week 03 (Figure 4). Cumulative influenza virus detections by type/subtype to date are as follows: 88.0% influenza A [34.5% A(H3), 4.4% A(H1N1)pdm09 and 61.1% A(unsubtyped)] and 12.0% influenza B (Table 1).
Detailed information on age and type/subtype has been received for 23,293 cases to date this season (Table 2). The proportion of cases by age group is as follows: 14.0% <5 years; 9.6% between 5-19 years; 15.7% between 20-44 years; 17.0% between 45-64 years of age; 43.7% ≥65 years.
The percentage of positive tests for rhinovirus continued its slow increase since week 01 to 11.3% in week 16. The percentage of positive tests for parainfluenza (5.3%) has also been increasing gradually over the past 8-10 weeks. The percentage of tests positive for respiratory syncytial virus (RSV) (6.4%) continued its decline from a peak in week 08. The percentage of positive tests for human metapneumovirus (hMPV) (5.0%) decreased for the second week in a row, and the percentage of positive tests for coronavirus (1.8%) has been decreasing slowly since week 04 (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(April 14 to April 20, 2013)
</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to April 20, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B
</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B
</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*
</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*
</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">23</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1898</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1448</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">211</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">239</TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">374</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">7</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">7</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">36</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2326</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1760</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">423</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">143</TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">650</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">3</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">1</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">14</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">831</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">475</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">73</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">283</TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">237</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">1</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">2</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">655</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">78</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">567</TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">70</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">13</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">3</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">7</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">3</TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">73</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8220</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3771</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">352</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4097</TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">724</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>

</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">11</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">11</TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">193</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9774</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">32</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9196</TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1527</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>

</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">3</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">1</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">12</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1853</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">771</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">65</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1017</TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">37</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>

</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">1</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">2</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">382</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">7</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">210</TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">6</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>

</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">111</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">76</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">5</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">30</TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>

</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">714</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">152</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">562</TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">15</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">42</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">4</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">16</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">22</TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">355</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">26764</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9242</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1178</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16344</TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">3641</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(April 14 to April 20, 2013)
</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to April 20, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively. </TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">3</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">3</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br2 bc1 bc7">49</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">2648</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">207</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">849</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1592</TD><TD class=alignRight headers="br1 br2 bc8 bc14">617</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br3 bc1 bc7">52</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1450</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">66</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">630</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">754</TD><TD class=alignRight headers="br1 br3 bc8 bc14">795</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">7</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">2</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">2</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">3</TD><TD class=alignRight headers="br1 br4 bc1 bc7">29</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3143</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">319</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1207</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1617</TD><TD class=alignRight headers="br1 br4 bc8 bc14">512</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">4</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">4</TD><TD class=alignRight headers="br1 br5 bc1 bc7">31</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3442</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">300</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1196</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">1946</TD><TD class=alignRight headers="br1 br5 bc8 bc14">510</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">4</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">4</TD><TD class=alignRight headers="br1 br6 bc1 bc7">64</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">9579</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">120</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3599</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">5860</TD><TD class=alignRight headers="br1 br6 bc8 bc14">597</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br7 bc1 bc7">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">167</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">20</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">145</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">2</TD><TD class=alignRight headers="br1 br7 bc8 bc14">0</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">18</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">5</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">2</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">11</TD><TD class=alignRight headers="br1 br8 bc1 bc7">225</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">20429</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">1032</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">7626</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">11771</TD><TD class=alignRight headers="br1 br8 bc8 bc14">3031</TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza strain characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 1097 influenza viruses. The 560 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 186 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 283 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 68 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =1097

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral resistance

During the 2012-13 season, NML has tested 1013 influenza viruses for resistance to oseltamivir, and 1010 influenza viruses for resistance to zanamivir. Among these, one A(H3N2) virus was resistant to oseltamivir and zanamivir. A total of 1110 influenza A viruses were tested for amantadine resistance and all but one were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">554</TD><TD class=alignRight headers="cr2 cc3">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc5">554</TD><TD class=alignRight headers="cr2 cc6">1 (0.2%)</TD><TD class=alignRight headers="cr2 cc8">915</TD><TD class=alignRight headers="cr2 cc9">914 (99.9%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">164</TD><TD class=alignRight headers="cr3 cc3">0</TD><TD class=alignRight headers="cr3 cc5">161</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">195</TD><TD class=alignRight headers="cr3 cc9">195 (100%)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">295</TD><TD class=alignRight headers="cr4 cc3">0</TD><TD class=alignRight headers="cr4 cc5">295</TD><TD class=alignRight headers="cr4 cc6">0</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">1013</TD><TD class=alignRight headers="cr5 cc3">0</TD><TD class=alignRight headers="cr5 cc5">1010</TD><TD class=alignRight headers="cr5 cc6">0</TD><TD class=alignRight headers="cr5 cc8">1110</TD><TD class=alignRight headers="cr5 cc9">1109 (99.9%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate was stable at 16.1 ILI consultations per 1,000 patient visits in week 16, and remains within the expected range (Figure 7). In week 16, the highest consultation rate was observed in children 5 to 19 years of age (46.9/1,000).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)



Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

In week 16, 21 laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalizations were reported by the Immunization Monitoring Program Active (IMPACT) network, compared to 16 in week 15. All but one of the cases reported in week 16 were identified with influenza B. The age distribution is as follows: 3 (14.3%) between 0-5 months, 5 (23.8%) between 6-23 months, 7 (33.3%) 2-4 years of age, 4 (19.0%) 5-9 years of age and 2 (9.5%) 10-16 years of age. Five cases were admitted to an intensive care unit (ICU) during week 16, three children 6-23 months of age and two 2-4 years of age, all with influenza B. One death was reported in week 16, a child 6-23 months of age with an underlying condition, infected with influenza B.
Since the start of the 2012-13 season, a total of 820 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 615 (75.0%) with influenza A [of which 121 (19.7%) were A(H3N2), 22 (3.6%) were A(H1N1)pdm09 and the remaining 472 were A(unsubtyped); and 205 (25.0%) with influenza B. The distribution of cases by age group is as follows: 152 (18.5%) <6 months of age; 194 (23.7%) age 6-23 months; 234 (28.5%) age 2-4 years; 171 (20.9%) age 5-9 years; and 69 (8.4%) age 10-16 years. Eighty-five (10.4%) of the 820 cases were admitted to the ICU. Of the 61 ICU admissions with available data, 53 (86.9%) cases had at least one co-morbidity. One death has been reported to date this season.
Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associate paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

In week 16, seven laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations were reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network, compared to 16 in week 15. Four of the seven hospitalizations were cases of influenza B, and three were untyped. Three cases were ≥65 years of age, two were 45-64 years of age, and two were 20-44 years of age. No ICU admissions or deaths were reported in week 16.

From November 4, 2012 to April 20, 2013, 1,735 influenza-associated adult hospitalizations were reported by the PCIRN-SOS network: 1,590 (91.6%) with influenza A [of which 305 were A(H3N2), 16 were A(H1N1)pdm09, and 1,269 were A(unsubtyped)]; 94 (5.4%) with influenza B, and the type has not been reported for 51 cases. The age distribution of hospitalizations is as follows: 1,193 (68.8%) were ≥65 years of age, 349 (20.1%) were 45-64 years, 185 (10.7%) were 20-44 years, and 8 (0.5%) were <20 years of age. ICU admission was required for 201 hospitalizations; the majority of which were adults ≥65 years of age (121; 60.2%). Of the ICU admissions, 82 (40.8%) had at least one co-morbidity, three (1.5%) had no co-morbidities, and 116 had no information to date. A total of 112 deaths have been reported: 26 with influenza A(H3N2), one with A(H1N1)pdm09, 79 with A(unsubtyped), 5 with influenza B, and one untyped. More than 85% of the deaths (96/112) were in adults ≥65 years of age, 13 (11.6%) were adults 45-64 years of age, and 3 (2.7%) were 20-44 years of age. Fifty-one (45.5%) deaths occurred in individuals who had at least one co-morbidity. Detailed clinical information on co-morbidities is not known for the remaining cases.
Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associate adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)

In week 16, 126 laboratory-confirmed influenza-associated hospitalizations were reported from participating provinces and territories<SUP>*</SUP>. The majority of cases were influenza A (67.5%). The highest proportion of hospitalisations were in adults ≥65 years of age (53.2%), followed by adults 45-64 years of age (15.9%). Of the 21 cases with available data, three cases were admitted to the ICU: two 45-64 years of age and one 0-4 years of age. Five deaths were reported in week 16, four ≥65 years of age and one 45-64 years of age, all with influenza A.

To date this season, 4,489 influenza-associated hospitalizations have been reported, of which 91.0% have been influenza A. Of those subtyped (48.4%), influenza A(H3) was the predominant influenza strain. The cumulative proportion of hospitalizations with influenza B continues to increase (9.1% in week 16). Age information was available for 4,486 cases, and the age distribution is as follows: 2,429 (54.1%) were ≥65 years of age; 758 (16.9%) were 45-64 years of age; 400 (8.9%) were 20-44 years of age; 40 (0.9%) were 15-19 years of age; 199 (4.4%) were 5-14 years; and 660 (14.7%) were 0-4 years of age. Of the 1,200 cases with available data, there have been 190 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults 45-64 years of age, followed by adults ≥65 years of age (36.3% and 34.2%, respectively). To date, 286 deaths have been reported: 236 adults ≥65 years of age, 33 adults 45-64 years; 11 adults 20-44 years, one child 5-14 years of age, and 5 were children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

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International Influenza Update


WHO : The most recent WHO surveillance report (26 April 2013) summarizes global influenza surveillance data from week 15 (7-13 April 2013). In temperate regions of the northern hemisphere, influenza activity is near inter-seasonal levels, although persistent transmission is reported in many countries due to increasing detections of influenza B. Analysis from 12 European countries in the second week of April revealed levels of pooled all-cause mortality among adults ≥65 years of age higher than observed in the previous three years. Mortality data for younger age groups was similar to previous seasons. In northern Africa and the Middle East, influenza activity has been declining since late February. The timing and pattern of circulating virus types was similar to that seen in Europe, with A(H1N1)pdm09 predominant in most countries. The exception was Egypt where an earlier peak was reported, almost entirely associated with A(H3N2). Influenza activity continued to decrease in temperate regions of Asia since peaking at the end of January, although activity persists in China and the Republic of Korea. Influenza A(H3N2) has been the most commonly detected virus in northern Asia this season although in northern China A(H1N1)pdm09 was predominant in the second half of the season. In tropical regions of Asia, influenza activity was low, with co-circulation of all three types/subtypes.
Transmission in India and Sri Lanka appears to have peaked in late March. In southern China, no overall increases in ILI activity have been noted since the appearance of A(H7N9) in Shanghai. In Central America and the Caribbean, a few countries reported low-level circulation of influenza A, but most cases of ILI were associated with other respiratory viruses (predominantly RSV). In Tropical South America Brazil and Ecuador reported increasing influenza A activity in the past several weeks. A few countries in tropical areas of Central Africa reported low-level but persistent influenza circulation with all three virus types. Influenza activity in temperate countries of the southern hemisphere is at inter-seasonal levels.

• World Health Organization influenza update

United States : During week 16, influenza activity decreased. Three states reported widespread influenza activity, 3 states reported regional influenza activity, and 8 states reported local activity. The national percentage of outpatient visits for ILI was 1.1%, which is below the national baseline. All 10 regions reported ILI below region-specific baseline levels and all states reported low or minimal ILI activity in week 16. The percentage of deaths due to pneumonia and influenza was at or above the epidemic threshold between weeks 01 and 12, but has been below the epidemic threshold for the past three weeks, and was 6.7% in week 16. The proportion of tests positive for influenza viruses declined to 7.4% in week 16. Of the positive influenza detections, 64.8% were influenza B. Since October 1, 2012, the CDC has antigenically characterized 2,209 influenza viruses. Among influenza A(H3N2) viruses, 1,260 (99.7%) were A/Victoria/361/2011-like, and 4 (0.3%) showed reduced titers to A/Victoria/361/2011 antiserum. Among influenza A(H1N1)pdm09 viruses, 207 (98.6%) were A/California/7/2009-like, and 3 (1.4%) showed reduced titers to A/California/7/2009-like antiserum. Among influenza B viruses, 494 (67.2%) were B/Wisconsin/01/2010-like belonging to the Yamagata lineage of viruses; and 241 (32.8%) to the B/Victoria lineage. Two (0.4%) A(H1N1)pdm09 and two (0.1%) A(H3N2) oseltamivir-resistant viruses have been reported to date this season. Among the 12,250 influenza-associated hospitalizations reported to date this season, 79.4% were associated with influenza A of which 96.1% were A(H3N2), and 50% were among adults ≥65 years. A total of 131 influenza-associated paediatric deaths have been reported to date this season, 61 with influenza A, 68 with influenza B and one with both influenza A and B.

• Centers for Disease Control and Prevention seasonal influenza report

Europe: In week 16, influenza activity is below seasonal thresholds in most countries. Most countries reported low intensity of ILI/ARI activity and a stable or decreasing trend. The percentage of sentinel specimens positive for influenza continues to decline to 23% in week 16. The proportion of influenza B detections has increased from 24% in week 03 to 57% in week 16. Among influenza A viruses in week 16, 67% were A(H3N2) and 33% were A(H1N1)pdm09. Since the beginning of the season, 63% of detections from sentinel and non-sentinel sources were influenza A [67% A(H1N1)pdm09 and 33% A(H3N2)] and 37% were influenza B. Among the 623 A(H1N1)pdm09 viruses tested for resistance to oseltamivir from 12 countries, 13 (2%) were found to contain the H275Y mutation: four were specimens from hospitalized and outpatients not exposed(3) or with unknown(1) exposure to oseltamivir, while the other nine viruses were detected in hospitalized and/or immunocompromised patients receiving oseltamivir treatment. The number of hospitalizations for severe acute respiratory illness (SARI) and the number positive for influenza have returned to pre-season levels in most participating countries.

• EuroFlu weekly electronic bulletin

Emerging Respiratory Pathogens

Human Avian Influenza


Influenza A(H7N9): Between April 19 and April 26, the WHO reported an additional 22 cases of avian influenza A(H7N9) in eastern China. The WHO reported the first case in Shandong province on 23 April 2013, and the Taipei Centres for Disease Control, Taiwan, has reported a travel-related case of avian influenza A(H7N9). The individual was working in the Jiangsu province, became ill shortly after arriving in Taiwan, and was subsequently diagnosed with avian influenza A(H7N9). This individual likely acquired the infection in mainland China. The public health risk posed avian influenza A(H7N9) from China to Canada is considered low at this time. Since March 2013, 109 cases, of which 22 were fatalities, of avian influenza A(H7N9) have been reported from six regions and two municipalities. The numbers of cases (and deaths) by jurisdiction is as follows: Anhui 4 (1), Henan 3 (0), Jiangsu 23 (3), Shandong 1 (0), Zhejiang 42 (6), Beijing 1 (0), Shanghai 34 (12) and Taiwan 1 (0). More than 1,800 close contacts of confirmed cases are being closely monitored. Some of the confirmed cases had contact with animals or with an animal environment. Investigations into the source and route of transmission are still in progress, but there has been no evidence of ongoing person-to-person spread. WHO is in contact with national authorities and is following the event closely.

• PHAC – H7N9 avian influenza
• PHAC – A(H7N9) risk assessment
• WHO Influenza at the human-animal interface
• WHO Disease Outbreak News
• WHO Frequently Asked Questions on human infection with influenza A(H7N9)

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http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Week 15

FluWatch report: April 7 to April 13, 2013 (Week 15)

Posted 2013-04-19For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w15_13/pdf/fw2013-15-eng.pdf">FluWatch report: April 7 to April 13, 2013 (Week 15) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• The percentage of laboratory tests positive for influenza has been stable at approximately 12% over the past five weeks. Detections of influenza B continued to increase, with influenza B detected in 81.1% of positive specimens in week 15.
• The number of regions reporting widespread or localized activity decreased compared to the previous week.
• The ILI consultation rate decreased and was within the expected range for this time of year.
• Detections of rhinovirus and human metapneumovirus (hMPV) continued to increase slowly while detections of other respiratory viruses were stable or decreasing.

Influenza Activity (geographic spread) and Outbreaks

In week 15, no regions reported widespread activity and seven regions [ AB(1), ON(5) and NS (1)] reported localized activity. The number of regions reporting widespread or localized activity declined compared to the previous week and continued to follow the overall decline in influenza/ILI activity from the peak in early January (Figures 1 and 2). Seven new influenza outbreaks were reported: four in long-term-care facilities, one in a hospital, and two in other facilities or communities (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 15





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=56)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The percentage of positive influenza tests increased slightly from 11.4% in week 14 to 12.4% in week 15 (Figure 4). Among the influenza viruses detected in week 15 (n=444), 18.9% were positive for influenza A viruses [of which 32.1% were A(H1N1)pdm09, 13.1% were A(H3), and 54.8% were A(unsubtyped)] (Table 1). Detections of influenza B increased to 81.1% of positive influenza detections in week 15, continuing the upward trend observed since week 03 (Figure 4). Cumulative influenza virus detections by type/subtype to date are as follows: 89.1% influenza A [34.6% A(H3), 4.4% A(H1N1)pdm09 and 61.1% A(unsubtyped)] and 10.9% influenza B (Table 1).
Detailed information on age and type/subtype has been received for 21,821 cases from 26 August 2012 to 23 March 2013 (Table 2). The proportion of cases by age group is as follows: 13.6% <5 years; 9.0% between 5-19 years; 15.5% between 20-44 years; 16.9% between 45-64 years of age; 45.0% ≥65 years.
The percentage of tests positive for RSV decreased to 8.9% in week 15, continuing its decline from a peak in week 08. The percentage of positive tests for rhinovirus continued its slow increase since week 01 to 10.1% in week 15. The percentage of positive tests for hMPV (6.2%) and parainfluenza (4.7%) have also been increasing gradually over the past 8-10 weeks. The percentage of positive tests for coronavirus (2.2%) has been decreasing slowly since week 04 (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(April 7 to April 13, 2013)
</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to April 13, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B
</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B
</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*
</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*
</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">9</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">3</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">4</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">20</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1900</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1449</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">214</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">237</TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">350</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">10</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">3</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">5</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">49</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2319</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1760</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">415</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">144</TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">612</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">1</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">1</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">27</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">828</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">474</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">73</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">281</TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">223</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">1</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">3</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">654</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">78</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">566</TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">68</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">21</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">4</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">11</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">6</TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">62</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8207</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3768</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">345</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4094</TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">648</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>

</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">18</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">1</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">17</TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">194</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9763</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">32</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9185</TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1334</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>

</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">8</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">1</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">3</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">4</TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">4</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1850</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">771</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">64</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1015</TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">25</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>

</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">13</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">13</TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">1</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">380</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">6</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">209</TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">4</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>

</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">2</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">111</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">76</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">5</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">30</TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>

</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">1</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">714</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">152</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">562</TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">15</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">84</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">11</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">27</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">46</TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">360</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">26726</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9239</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1164</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16323</TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">3280</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(March 17 to March 23, 2013)
</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to March 23, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively. </TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">12</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">3</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">9</TD><TD class=alignRight headers="br1 br2 bc1 bc7">43</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">2589</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">183</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">843</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1563</TD><TD class=alignRight headers="br1 br2 bc8 bc14">379</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">2</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">2</TD><TD class=alignRight headers="br1 br3 bc1 bc7">45</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1428</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">64</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">628</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">736</TD><TD class=alignRight headers="br1 br3 bc8 bc14">538</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">19</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">4</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">2</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">13</TD><TD class=alignRight headers="br1 br4 bc1 bc7">32</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3062</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">289</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1192</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1581</TD><TD class=alignRight headers="br1 br4 bc8 bc14">319</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">16</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">15</TD><TD class=alignRight headers="br1 br5 bc1 bc7">36</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3375</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">275</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1191</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">1909</TD><TD class=alignRight headers="br1 br5 bc8 bc14">315</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">31</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">4</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">26</TD><TD class=alignRight headers="br1 br6 bc1 bc7">36</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">9476</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">102</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3583</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">5791</TD><TD class=alignRight headers="br1 br6 bc8 bc14">340</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">1</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br7 bc1 bc7">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">166</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">20</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">144</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">2</TD><TD class=alignRight headers="br1 br7 bc8 bc14">0</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">81</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">10</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">6</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">65</TD><TD class=alignRight headers="br1 br8 bc1 bc7">192</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">20096</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">933</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">7581</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">11582</TD><TD class=alignRight headers="br1 br8 bc8 bc14">1891</TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza strain characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 1016 influenza viruses. The 553 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 162 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 248 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 53 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =1016

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral resistance

During the 2012-13 season, NML has tested 941 influenza viruses for resistance to oseltamivir, and 942 influenza viruses for resistance to zanamivir. All viruses tested were sensitive to oseltamivir and zanamivir. A total of 1029 influenza A viruses were tested for amantadine resistance and all but one were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">528</TD><TD class=alignRight headers="cr2 cc3">0</TD><TD class=alignRight headers="cr2 cc5">532</TD><TD class=alignRight headers="cr2 cc6">0</TD><TD class=alignRight headers="cr2 cc8">855</TD><TD class=alignRight headers="cr2 cc9">854 (99.9 %)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">156</TD><TD class=alignRight headers="cr3 cc3">0</TD><TD class=alignRight headers="cr3 cc5">153</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">174</TD><TD class=alignRight headers="cr3 cc9">174 (100 %)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">257</TD><TD class=alignRight headers="cr4 cc3">0</TD><TD class=alignRight headers="cr4 cc5">257</TD><TD class=alignRight headers="cr4 cc6">0</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">941</TD><TD class=alignRight headers="cr5 cc3">0</TD><TD class=alignRight headers="cr5 cc5">942</TD><TD class=alignRight headers="cr5 cc6">0</TD><TD class=alignRight headers="cr5 cc8">1029</TD><TD class=alignRight headers="cr5 cc9">1028 (99.9 %)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate decreased from 23.8 ILI consultations per 1,000 patient visits in week 14, to 16.4 in week 15 and remains within the expected range (Figure 7). In week 15, the highest consultation rate was observed in children 5 to 19 years of age (28.1/1,000).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)



Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

In week 15, 12 laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalizations were reported by the Immunization Monitoring Program Active (IMPACT) network, compared to 15 in week 14. All the cases reported in week 15 were identified with influenza B. The age distribution is as follows: one (8.3%) between 0-5 months, 2 (16.7%) between 6-23 months, 4 (33.3%) 2-4 years of age, 3 (25.0%) 5-9 years of age and 2 (16.7%) 10-16 years of age. One admission to an intensive care unit (ICU) was reported during week 15, a child 6-23 months of age with influenza B.

Since the start of the 2012-13 season, a total of 796 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 615 (77.3%) with influenza A [of which 121 (19.7%) were A(H3N2), 22 (3.6%) were A(H1N1)pdm09 and the remaining 472 were A(unsubtyped); and 181 (22.7%) with influenza B. The distribution of cases by age group is as follows: 148 (18.6%) <6 months of age; 189 (23.7%) age 6-23 months; 227 (28.5%) age 2-4 years; 166 (20.9%) age 5-9 years; and 66 (8.3%) age 10-16 years. Seventy-six (9.5%) of the 796 cases were admitted to the ICU. No deaths have been reported to date.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associate paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

In week 15, 13 laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations were reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network, compared to 12 in week 14. Seven of the 13 hospitalizations were cases of influenza A(unsubtyped), and six were influenza B. Seven cases were ≥65 years of age, and six were 45-64 years of age. No ICU admissions were reported during the current week. One death was reported, a person ≥65 years of age with influenza A(H1N1)pdm09.

From November 4, 2012 to April 13, 2013, 1,700 influenza-associated adult hospitalizations were reported by the PCIRN-SOS network: 1,565 (92.1%) with influenza A [of which 300 were A(H3N2), 16 were A(H1N1)pdm09, and 1,249 were A(unsubtyped)]; 87 (5.1%) with influenza B, and the type has not been reported for 48 cases. The age distribution of hospitalizations is as follows: 1,176 (69.2%) were ≥65 years of age, 341 (20.1%) were 45-64 years, 175 (10.3%) were 20-44 years, and 8 (0.5%) were <20 years of age. ICU admission was required for 196 hospitalizations; the majority of which were adults ≥65 years of age (119; 60.7%). Of the ICU admissions, 79 (40.3%) had at least one co-morbidity, three (1.5%) had no co-morbidities, and 114 had no information to date. A total of 105 deaths have been reported: 24 with influenza A(H3N2), one with A(H1N1)pdm09, 74 with A(unsubtyped), 5 with influenza B, and one untyped. More than 80% of the deaths (90/105) were in adults ≥65 years of age, 12 (11.4%) were adults 45-64 years of age, and 3 (2.9%) were 20-44 years of age.
Forty-seven (44.8%) deaths occurred in individuals who had at least one co-morbidity. Detailed clinical information on co-morbidities is not known for the remaining cases.

Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associate adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.
Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)

In week 15, 91 laboratory-confirmed influenza-associated hospitalizations were reported from participating provinces and territories<SUP>*</SUP>. The majority of cases were influenza A (52.7%). The highest proportion of hospitalisations were in adults ≥65 years of age (37.4%), followed by adults 45-64 years of age (33.0%). Of the 25 cases with available data, four cases were admitted to the ICU: three 45-64 years of age and one 20-44 years of age. No deaths were reported in week 15.

To date this season, 4,341 influenza-associated hospitalizations have been reported, of which 91.9% have been influenza A. Of those subtyped (48.4%), influenza A(H3) was the predominant influenza strain. The cumulative proportion of hospitalizations with influenza B continues to increase (8.1% in week 15). Age information was available for 4,338 cases, and the age distribution is as follows: 2,350 (54.2%) were ≥65 years of age; 737 (17.0%) were 45-64 years of age; 387 (8.9%) were 20-44 years of age; 40 (0.9%) were 15-19 years of age; 186 (4.3%) were 5-14 years; and 638 (14.7%) were 0-4 years of age. Of the 1,157 cases with available data, there have been 184 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults 45-64 years of age, followed by adults ≥65 years of age (36.9% and 33.2%, respectively). To date, 280 deaths have been reported: 232 were adults ≥65 years of age, 31 were adults 45-64 years; 11 were adults 20-44 years, one was a child 5-14 years of age, and 5 were children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

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International Influenza Update


WHO : The most recent WHO surveillance report (12 April 2013) summarizes global influenza surveillance data from week 13 (24 to 30 March 2013). In North America, the peak of influenza activity in Mexico occurred about 2 weeks after the early-January peak in Canada and the United States. Although the United States reported a greater proportion of influenza B this season, both Canada and the US have seen an increase in circulation of influenza B in the later part of the season. Analysis from 12 European countries revealed a broad peak of excess mortality among older adults, starting in early January, comparable with the mortality levels observed during the 2011-2012 season. In northern Africa and the western Asia region, the peak of influenza activity occurred in late February with a predominance of A(H1N1)pdm09. Influenza activity continued to decrease in temperate regions of Asia since peaking at the end of January, although activity in China and the Republic of Korea peaked a few weeks later than in other countries. Influenza A(H3N2) has been the most commonly detected virus in northern Asia this season although in northern China an increasing proportion of A(H1N1)pdm09 has been detected. In tropical regions of Asia, influenza activity was low, with circulation primarily of A(H3N2) and A(H1N1)pdm09 in India and all three types/subtypes in Sri Lanka. In Central America and the Caribbean, influenza activity was similar to recent weeks, with RSV the most commonly detected agent among cases of acute respiratory illness. Countries in Tropical South America reported low numbers of influenza detections. Most countries in tropical areas of Central Africa reported low-level but persistent influenza circulation with all three virus types. Influenza activity in temperate countries of the southern hemisphere is at inter-seasonal levels.

• World Health Organization influenza update

United States : No new influenza surveillance update has been published by the CDC since 6 April 2013.

• Centers for Disease Control and Prevention seasonal influenza report

Europe: In week 15, ILI and acute respiratory illness (ARI) consultation rates are below the baseline or at pre-season levels in many countries. Most countries reported low intensity of ILI/ARI activity and a decreasing trend. The percentage of sentinel specimens positive for influenza continues to decline to 27% in week 15. The proportion of influenza B detections has increased from 24% in week 03 to 56% in week 15. Influenza B now dominates in circulation although overall detections of influenza are declining. Among influenza A viruses in week 15, 54% were A(H3N2) and 46% were A(H1N1)pdm09. Since the beginning of the season, 64% of detections from sentinel and non-sentinel sources were influenza A [68% A(H1N1)pdm09 and 32% A(H3N2)] and 36% were influenza B. In week 15, the number of countries reporting a predominance of influenza A circulation continued to decrease, and now includes only Greece, Ireland, the United Kingdom, Belgium, Finland, Italy and some parts of the Russian Federation. Among the 623 A(H1N1)pdm09 viruses tested for resistance to oseltamivir from 12 countries, 13 (2%) were found to contain the H275Y mutation: four were specimens from hospitalized and outpatients not exposed(3) or with unknown(1) exposure to oseltamivir, while the other nine viruses were detected in hospitalized and/or immunocompromised patients receiving oseltamivir treatment. The number of hospitalizations for severe acute respiratory illness (SARI) are declining, in keeping with ILI/ARI consultation rates.

• EuroFlu weekly electronic bulletin

Emerging Respiratory Pathogens

Human Avian Influenza

Influenza A(H7N9): Between April 12 and April 19, the WHO reported an additional 49 cases of avian influenza A(H7N9) in eastern China. Of these cases, five were discovered retrospectively. Since March 2013, 87 cases, of which 17 were fatalities, of avian influenza A(H7N9) have been reported from four provinces and two municipalities. The numbers of cases (and deaths) by jurisdiction is as follows: Anhui 3 (1), Henan 3 (0), Jiangsu 21 (3), Zhejiang 27 (2), Beijing 1 (0) and Shanghai 32 (11). More than 1,000 close contacts of confirmed cases are being closely monitored. Some of the confirmed cases had contact with animals or with an animal environment. Investigations into the source and route of transmission are still in progress, but there has been no evidence of ongoing person-to-person spread. WHO is in contact with national authorities and is following the event closely.

• PHAC – H7N9 avian influenza
• WHO Influenza at the human-animal interface
• WHO Disease Outbreak News
• WHO Frequently Asked Questions on human infection with influenza A(H7N9)

Human Swine Influenza

No new human cases of infection with swine influenza viruses or variants were reported in week 14.

• Centers for Disease Control and Prevention seasonal influenza report

.../
http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Week 14

FluWatch report: March 31 to April 6, 2013 (Week 14)

Posted 2013-04-12For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w14_13/pdf/fw2013-14-eng.pdf">FluWatch report: March 31 to April 6, 2013 (Week 14) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• Overall influenza activity continued to decline in week 14.
• Laboratory detections of influenza decreased slightly compared to the past 2 weeks. Detections of influenza B also decreased, although influenza B continued to represent 72.7% of positive specimens in week 14.
• The number of regions reporting widespread or localized activity was the same as in the previous week.
• The ILI consultation rate increased but was within the expected range for this time of year.
• Detections of RSV and human metapneumovirus (hMPV) increased while detections of other respiratory viruses were stable or decreasing.

Influenza Activity (geographic spread) and Outbreaks

In week 14, no regions reported widespread activity and 11 regions [in BC(1), AB(1), SK(1), ON(5), QC(1), NS (1) and NL(1)] reported localized activity. The number of regions reporting widespread or localized activity was the same as the previous week and continued to follow the overall decline in influenza/ILI activity from the peak in early January (Figures 1 and 2). Eight new influenza outbreaks were reported: seven in long-term-care facilities and one in another facility or community (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 14





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=56)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The percentage of positive influenza tests declined slightly to 11.1% in week 14 (Figure 4). Among the influenza viruses detected in week 14 (n=429), 27.3% were positive for influenza A viruses [of which 20.5% were A(H1N1)pdm09, 15.4% were A(H3), and 64.1% were A(unsubtyped)](Table 1). Detections of influenza B decreased after rising over the past 10 weeks, and influenza B was detected in 72.7% of positive influenza detections in week 14 (Figure 4). Cumulative influenza virus detections by type/subtype to date are as follows: 90.1% influenza A [34.6% A(H3), 4.2% A(H1N1)pdm09 and 61.2% A(unsubtyped)] and 9.9% influenza B (Table 1).
Detailed information on age and type/subtype has been received for 21,821 cases from 26 August 2012 to 23 March 2013 (Table 2). The proportion of cases by age group is as follows: 13.6% <5 years; 9.0% between 5-19 years; 15.5% between 20-44 years; 16.9% between 45-64 years of age; 45.0% ≥ 65 years.
The percentage of tests positive for RSV decreased slightly to 11.3% in week 14, continuing its decline from a peak in week 08. The percentage of positive tests for hMPV increased sharply to 7.4% while the percentage of positive tests for rhinovirus continued its slow increase since week 01 to 9.1% in week 14. The percentage of positive tests decreased slightly for parainfluenza (3.4%), coronavirus (3.0%) and adenovirus (0.8%) (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(March 31 to April 6, 2013)
</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to April 6, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B
</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B
</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*
</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*
</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">13</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">5</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">4</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">4</TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">8</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1894</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1448</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">207</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">239</TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">331</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">9</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">4</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">2</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">3</TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">64</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2307</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1755</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">405</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">147</TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">554</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">5</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">3</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">26</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">827</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">474</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">72</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">281</TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">196</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">12</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">12</TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">5</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">653</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">78</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">565</TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">65</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">36</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">4</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">11</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">21</TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">65</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8184</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3763</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">329</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4092</TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">585</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>

</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">17</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">17</TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">136</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9750</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">31</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9173</TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1164</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>

</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">14</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">2</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">4</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">8</TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">7</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1842</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">770</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">61</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1011</TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">21</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>

</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">6</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">6</TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">367</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">6</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">196</TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">3</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>

</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">3</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">3</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">109</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">76</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">3</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">30</TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>

</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">1</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">713</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">152</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">561</TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">15</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">117</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">18</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">24</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">75</TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">312</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">26646</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9227</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1124</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16295</TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">2935</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(March 17 to March 23, 2013)
</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to March 23, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively. </TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">12</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">3</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">9</TD><TD class=alignRight headers="br1 br2 bc1 bc7">43</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">2589</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">183</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">843</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1563</TD><TD class=alignRight headers="br1 br2 bc8 bc14">379</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">2</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">2</TD><TD class=alignRight headers="br1 br3 bc1 bc7">45</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1428</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">64</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">628</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">736</TD><TD class=alignRight headers="br1 br3 bc8 bc14">538</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">19</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">4</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">2</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">13</TD><TD class=alignRight headers="br1 br4 bc1 bc7">32</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3062</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">289</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1192</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1581</TD><TD class=alignRight headers="br1 br4 bc8 bc14">319</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">16</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">15</TD><TD class=alignRight headers="br1 br5 bc1 bc7">36</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3375</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">275</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1191</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">1909</TD><TD class=alignRight headers="br1 br5 bc8 bc14">315</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">31</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">4</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">26</TD><TD class=alignRight headers="br1 br6 bc1 bc7">36</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">9476</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">102</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3583</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">5791</TD><TD class=alignRight headers="br1 br6 bc8 bc14">340</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">1</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br7 bc1 bc7">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">166</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">20</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">144</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">2</TD><TD class=alignRight headers="br1 br7 bc8 bc14">0</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">81</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">10</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">6</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">65</TD><TD class=alignRight headers="br1 br8 bc1 bc7">192</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">20096</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">933</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">7581</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">11582</TD><TD class=alignRight headers="br1 br8 bc8 bc14">1891</TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza strain characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 938 influenza viruses. The 522 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 155 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 209 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 52 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =938

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral resistance

During the 2012-13 season, NML has tested 900 influenza viruses for resistance to oseltamivir, and 902 influenza viruses for resistance to zanamivir. All viruses tested were sensitive to oseltamivir and zanamivir. A total of 1017 influenza A viruses were tested for amantadine resistance and all but one were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignRight headers="cr2 cc2">508</TD><TD class=alignRight headers="cr2 cc3">0</TD><TD class=alignRight headers="cr2 cc5">510</TD><TD class=alignRight headers="cr2 cc6">0</TD><TD class=alignRight headers="cr2 cc8">849</TD><TD class=alignRight headers="cr2 cc9">848 (99.9 %)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignRight headers="cr3 cc2">151</TD><TD class=alignRight headers="cr3 cc3">0</TD><TD class=alignRight headers="cr3 cc5">151</TD><TD class=alignRight headers="cr3 cc6">0</TD><TD class=alignRight headers="cr3 cc8">168</TD><TD class=alignRight headers="cr3 cc9">168 (100 %)</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignRight headers="cr4 cc2">241</TD><TD class=alignRight headers="cr4 cc3">0</TD><TD class=alignRight headers="cr4 cc5">241</TD><TD class=alignRight headers="cr4 cc6">0</TD><TD class=alignRight headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignRight headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignRight headers="cr5 cc2">900</TD><TD class=alignRight headers="cr5 cc3">0</TD><TD class=alignRight headers="cr5 cc5">902</TD><TD class=alignRight headers="cr5 cc6">0</TD><TD class=alignRight headers="cr5 cc8">1017</TD><TD class=alignRight headers="cr5 cc9">1016 (99.9 %)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate increased from 20.5 ILI consultations per 1,000 patient visits in week 13, to 23.4 in week 14 but remains within the expected range (Figure 7). In week 14, the highest consultation rate was observed in children 5 to 19 years of age (35.8/1,000).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)



Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

In week 14, 12 new laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalizations were reported by the Immunization Monitoring Program Active (IMPACT) network, compared to 25 in week 13. Among the cases reported in week 14, 11 were identified with influenza B and one with A(unsubtyped). For the sixth week in a row, the number of influenza B cases exceeded the number of influenza A cases, a reversal of the pattern seen earlier in the season. The age distribution is as follows: one (8.3%) between 0-5 months, 2 (16.7%) between 6-23 months, 5 (41.7%) 2-4 years of age, and 4 (33.3%) 5-9 years of age. No admissions to intensive care unit (ICU) were reported during week 14.

Since the start of the 2012-13 season, a total of 771 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 614 (79.6%) with influenza A [of which 118 (19.2%) were A(H3N2), 22 (2.9%) were A(H1N1)pdm09 and the remaining 474 were A(unsubtyped); and 157 (20.4%) with influenza B. The distribution of cases by age group is as follows: 144 (18.7%) <6 months of age; 187 (24.3%) age 6-23 months; 220 (28.5%) age 2-4 years; 157 (20.4%) age 5-9 years; and 63 (8.2%) age 10-16 years. Seventy-four (9.6%) of the 771 cases were admitted to the ICU. No deaths have been reported to date.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associate paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

In week 14, 12 laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations were reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network, compared to 10 in week 13. Six of the 12 hospitalizations were cases of influenza A(unsubtyped), five were influenza B and one was untyped. Four cases were ≥65 years of age, six were 45-64 years of age, and two were 20-44 years of age. No ICU admissions or deaths were reported during the current week.

From week 45 to week 14, 1,658 influenza-associated adult hospitalizations were reported by the PCIRN-SOS network: 1,528 (92.2%) with influenza A [of which 286 were A(H3N2), 15 were A(H1N1)pdm09, and 1,227 were A(unsubtyped)]; 76 (4.6%) with influenza B, and the type has not been reported for 54 cases. The age distribution of hospitalizations is as follows: 1,151 (69.4%) were ≥65 years of age, 327 (19.7%) were 45-64 years, 172 (10.4%) were 20-44 years, and 8 (0.5%) were <20 years of age. ICU admission was required for 190 hospitalizations; the majority of which were adults ≥65 years of age (114; 60.0%). Of the ICU admissions, 74 (38.9%) had at least one co-morbidity, three (1.6%) had no co-morbidities, and 113 had no information to date. A total of 104 deaths have been reported: 22 with influenza A(H3N2), 76 with influenza A(unsubtyped), 5 with influenza B, and one untyped. More than 80% of the deaths (89/104) were in adults ≥65 years of age, 12 (11.5%) were adults 45-64 years of age, and 3 (2.9%) were 20-44 years of age. Forty-four (42.3%) deaths occurred in individuals who had at least one co-morbidity. Detailed clinical information on co-morbidities is not known for the remaining cases.

Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associate adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths
(Aggregate Surveillance System<SUP>*</SUP>)

In week 14, 118 laboratory-confirmed influenza-associated hospitalizations were reported from participating provinces and territories<SUP>*</SUP>. The majority of cases were influenza A (78; 66.1%). The highest proportion of hospitalisations were in adults ≥65 years of age (37.3%), followed by adults 45-64 years of age (17.0%). Of the 26 cases with available data, four were admitted to the ICU: three children under 16 years of age, and one adult 45-64 years of age. Four deaths were reported in week 14: two adults aged 45-64 years and two ≥65 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

To date this season 4,249 influenza-associated hospitalizations have been reported, of which 92.8% have been influenza A. Of those subtyped (48.4%), influenza A(H3) was the predominant influenza strain. The cumulative proportion of hospitalizations with influenza B continues to increase (7.2% in week 14). Age information was available for 4,246 cases, and the age distribution is as follows: 2,316 were ≥65 years of age; 706 were 45-64 years of age; 378 were 20-44 years of age; 40 were 15-19 years of age; 182 were 5-14 years; and 624 were 0-4 years of age. Of the 1,131 cases with available data, there have been 180 hospitalisations for which admission to an ICU was required; the highest proportions have been in adults 45-64 years of age, followed by adults ≥65 years of age (36.1% and 33.9%, respectively). To date, 281 deaths have been reported: 232 were adults ≥65 years of age, 32 were adults 45-64 years; 11 were adults 20-44 years, one was a child 5-14 years of age, and 5 were children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

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International Influenza Update


WHO: No new influenza surveillance update has been published by WHO since 2 April 2013.

• World Health Organization influenza update

United States: During week 14, influenza activity decreased. Four states reported widespread influenza activity, 7 states reported regional influenza activity, and the District of Columbia, Puerto Rico and 14 states reported local activity. The national percentage of outpatient visits for ILI was 1.5%, which is below the national baseline. Two of 10 regions reported ILI at or above region-specific baseline levels but all states reported low or minimal ILI activity in week 14. The percentage of deaths due to pneumonia and influenza was at or above the epidemic threshold between weeks 01 and 12, but has been below the epidemic threshold for the past two weeks, and was 7.2% in week 14. The peak percentage of deaths due to pneumonia and influenza was observed in week 03 at 9.8%, which was higher than observed during the previous four seasons. The proportion of tests positive for influenza viruses declined to 10.9% in week 14. Of the positive influenza detections, 71.1% were influenza B. Since October 1, 2012, the CDC has antigenically characterized 2,098 influenza viruses. Among influenza A(H3N2) viruses, 1,196 (99.7%) were A/Victoria/361/2011-like, and 4 (0.3%) showed reduced titers to A/Victoria/361/2011 antiserum. Among influenza A(H1N1)pdm09 viruses, 206 (98.6%) were A/California/7/2009-like, and 3 (1.4%) showed reduced titers to A/California/7/2009-like antiserum. Among influenza B viruses, 474 (68.8%) were B/Wisconsin/01/2010-like belonging to the Yamagata lineage of viruses; and 215 (31.2%) to the B/Victoria lineage. Two (0.4%) A(H1N1)pdm09 and two (0.1%) A(H3N2) oseltamivir-resistant viruses have been reported to date this season. Among the 12,052 influenza-associated hospitalizations reported to date this season, 80.3% were associated with influenza A of which 96.2% were A(H3N2), and 50% were among adults ≥65 years. A total of 116 influenza-associated paediatric deaths have been reported to date this season, 57 with influenza A, 57 with influenza B and one with both influenza A and B.

• Centers for Disease Control and Prevention seasonal influenza report

Europe: In week 14, ILI and acute respiratory illness (ARI) consultation rates declined throughout the region. Most countries reported low intensity of ILI/ARI activity and a decreasing trend. The proportion of influenza B detections has increased from 24% in week 03 to 54% in week 14. Among influenza A viruses in week 14, 57% were A(H3N2) and 43% were A(H1N1)pdm09. Since the beginning of the season, 64% of detections from sentinel and non-sentinel sources were influenza A [68% A(H1N1)pdm09 and 32% A(H3N2)] and 36% were influenza B. Among influenza B viruses, 92% belonged to the Yamagata lineage and 8% to the Victoria lineage. In week 14, the number of countries reporting a predominance of influenza A circulation continued to decrease, and now includes only Greece, Ireland, the United Kingdom, Belgium, Estonia and Finland. Among the 593 A(H1N1)pdm09 viruses tested for resistance to oseltamivir from 12 countries, 10 were found to contain the H275Y mutation: three were specimens from hospitalized and outpatients not exposed to oseltamivir, while the other seven viruses were detected in hospitalized immunocompromised patients receiving oseltamivir treatment. The number of hospitalizations for severe acute respiratory illness (SARI) are declining, in keeping with ILI/ARI consultation rates.

• EuroFlu weekly electronic bulletin

Emerging Respiratory Pathogens

Human Avian Influenza


Influenza A(H7N9): Between April 6 and April 11, the WHO reported an additional 22 human cases of influenza A(H7N9) in eastern China, including two adults 20-44 years of age, six adults 45-64 years of age, and 14 adults ≥65 years of age. The most recent date of illness onset is 4 April 2013. Of these cases, two were fatal, 14 were hospitalized, and two had mild illness. The health status of four cases was not reported. Two earlier cases were also reported to have died. Since March 2013, a total of 38 cases of influenza A(H7N9) have been reported, with 10 deaths, 19 cases of severe illness, and nine cases of mild illness. More than 760 close contacts of confirmed cases are being closely monitored. Some of the confirmed cases had contact with animals or with an animal environment. Investigations into the source and route of transmission are still in progress, but there has been no evidence of ongoing person-to-person spread. WHO is in contact with national authorities and is following the event closely.

• PHAC – H7N9 avian influenza
• WHO Influenza at the human-animal interface
• WHO Disease Outbreak News
• WHO Frequently Asked Questions on human infection with influenza A(H7N9)

Human Swine Influenza

No new human cases of infection with swine influenza viruses or variants were reported in week 14.

• Centers for Disease Control and Prevention seasonal influenza report

Novel Coronavirus

No new cases of novel coronavirus (nCoV) have been reported by WHO since 26 March 2013. Since April 2012, 17 laboratory-confirmed cases of nCoV have been identified, including 11 deaths.

• PHAC – Coronavirus
• WHO – Coronavirus infections

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http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Week 13

FluWatch report: March 24 to March 30, 2013 (Week 13)

Posted 2013-04-05For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w13_13/pdf/fw2013-13-eng.pdf">FluWatch report: March 24 to March 30, 2013 (Week 13) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

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Overall Summary

• Overall influenza activity continued to decline. The number of regions reporting widespread or localized activity decreased in week 13.
• The ILI consultation rate increased slightly but was within the expected range for this time of year.
• Laboratory detections of influenza were similar to the past 2 weeks, and the proportion of influenza B continued to increase. Detections of other respiratory viruses were stable or decreasing compared to recent weeks.
• Between March 31 and April 5, the WHO reported 16 human cases of influenza A(H7N9) in China.

Influenza Activity (geographic spread) and Outbreaks

In week 13, one region in NL reported widespread activity and 10 regions [in AB(1), SK(1), MB(1), ON(3), QC(2), NS (1) and NL(1)] reported localized activity. The number of regions reporting widespread or localized activity decreased compared to the previous week and continued to follow the overall decline in influenza/ILI activity from the peak in early January (Figures 1 and 2). Fourteen new influenza outbreaks were reported: nine in long-term-care facilities, two in school and three in other facilities or communities (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 13





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=58)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The percentage of positive influenza tests was stable for the third week in a row at 12.2% in week 13 (Figure 4). Among the influenza viruses detected in week 13 (n=433), 25.9% were positive for influenza A viruses [of which 26.8% were A(H1N1)pdm09, 16.1% were A(H3), and 57.1% were A(unsubtyped)] (Table 1). The proportion of influenza B detections has increased over the past 10 weeks from 2.1% in week 03 to 74.1% in week 13 (Figure 4). Cumulative influenza virus detections by type/subtype to date are as follows: 91.0% influenza A [34.7% A(H3), 4.1% A(H1N1)pdm09 and 61.1% A(unsubtyped)] and 9.0% influenza B (Table 1).
Detailed information on age and type/subtype has been received for 21,821 cases from 26 August 2012 to 23 March 2013 (Table 2). The proportion of cases by age group is as follows: 13.6% < 5 years; 9.0% between 5-19 years; 15.5% between 20-44 years; 16.9% between 45-64 years of age; 45.0% ≥ 65 years.
The percentage of tests positive for RSV decreased to 11.8% in week 13, continuing its decline from a peak in week 08. The percentage of positive tests also decreased for rhinovirus (8.9%); and was stable for parainfluenza (3.8%), coronavirus (3.5%), hMPV (5.3%) and adenovirus (1.4%) (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(March 24 to March 30, 2013)
</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to March 30, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B
</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B
</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*
</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*
</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">4</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">3</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">1</TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">10</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1881</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1443</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">203</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">235</TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">323</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">16</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">5</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">8</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">3</TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">55</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2298</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1751</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">403</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">144</TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">490</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">9</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">7</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">19</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">822</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">474</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">69</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">279</TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">170</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">17</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">17</TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">4</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">641</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">78</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">10</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">553</TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">60</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">23</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">5</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">12</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">6</TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">56</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8148</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3758</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">318</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4072</TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">520</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>

</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">26</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">26</TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">172</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9733</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">31</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9156</TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">1028</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>

</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">9</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">5</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">2</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">2</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1828</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">768</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">57</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">1003</TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">14</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>

</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">6</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">1</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">5</TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">361</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">6</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">190</TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">3</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>

</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">106</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">73</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">3</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">30</TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>

</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">3</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">711</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">152</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">559</TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">14</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">112</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">18</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">30</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">64</TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">321</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">26529</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9208</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1100</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16221</TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">2623</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*
</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(March 17 to March 23, 2013)
</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to March 23, 2013)
</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively. </TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">12</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">3</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">9</TD><TD class=alignRight headers="br1 br2 bc1 bc7">43</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">2589</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">183</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">843</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1563</TD><TD class=alignRight headers="br1 br2 bc8 bc14">379</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">2</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">2</TD><TD class=alignRight headers="br1 br3 bc1 bc7">45</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1428</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">64</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">628</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">736</TD><TD class=alignRight headers="br1 br3 bc8 bc14">538</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">19</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">4</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">2</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">13</TD><TD class=alignRight headers="br1 br4 bc1 bc7">32</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3062</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">289</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1192</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1581</TD><TD class=alignRight headers="br1 br4 bc8 bc14">319</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">16</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">15</TD><TD class=alignRight headers="br1 br5 bc1 bc7">36</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3375</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">275</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1191</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">1909</TD><TD class=alignRight headers="br1 br5 bc8 bc14">315</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">31</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">4</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">26</TD><TD class=alignRight headers="br1 br6 bc1 bc7">36</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">9476</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">102</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3583</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">5791</TD><TD class=alignRight headers="br1 br6 bc8 bc14">340</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">1</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">1</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br7 bc1 bc7">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">166</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">20</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">144</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">2</TD><TD class=alignRight headers="br1 br7 bc8 bc14">0</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">81</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">10</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">6</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">65</TD><TD class=alignRight headers="br1 br8 bc1 bc7">192</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">20096</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">933</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">7581</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">11582</TD><TD class=alignRight headers="br1 br8 bc8 bc14">1891</TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza strain characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 902 influenza viruses. The 515 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 150 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 190 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 47 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N =902

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral resistance

During the 2012-13 season, NML has tested 835 influenza viruses for resistance to oseltamivir, and 833 influenza viruses for resistance to zanamivir. All viruses tested were sensitive to oseltamivir and zanamivir. A total of 937 influenza A viruses were tested for amantadine resistance and all were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignCenter headers="cr2 cc2">486</TD><TD class=alignCenter headers="cr2 cc3">0</TD><TD class=alignCenter headers="cr2 cc5">485</TD><TD class=alignCenter headers="cr2 cc6">0</TD><TD class=alignCenter headers="cr2 cc8">792</TD><TD class=alignCenter headers="cr2 cc9">792 (100%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignCenter headers="cr3 cc2">142</TD><TD class=alignCenter headers="cr3 cc3">0</TD><TD class=alignCenter headers="cr3 cc5">141</TD><TD class=alignCenter headers="cr3 cc6">0</TD><TD class=alignCenter headers="cr3 cc8">145</TD><TD class=alignCenter headers="cr3 cc9">145</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignCenter headers="cr4 cc2">207</TD><TD class=alignCenter headers="cr4 cc3">0</TD><TD class=alignCenter headers="cr4 cc5">207</TD><TD class=alignCenter headers="cr4 cc6">0</TD><TD class=alignCenter headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignCenter headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignCenter headers="cr5 cc2">835</TD><TD class=alignCenter headers="cr5 cc3">0</TD><TD class=alignCenter headers="cr5 cc5">833</TD><TD class=alignCenter headers="cr5 cc6">0</TD><TD class=alignCenter headers="cr5 cc8">937</TD><TD class=alignCenter headers="cr5 cc9">937 (100%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate increased from 11.3 ILI consultations per 1,000 patient visits in week 12, to 21.2 in week 13 but remains within the expected range (Figure 7). In week 13, the highest consultation rate was observed in children less than 5 years of age (47.9/1,000).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)



Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)
Pharmacy Surveillance

Pharmacy surveillance has been concluded for the 2012-13 influenza season. The antiviral prescription rate peaked in week 01 at 343.9 antiviral prescriptions per 100,000 new prescriptions dispensed. From week 52, 2012 to week 11, 2013, the proportion of prescriptions for influenza antivirals was highest among seniors ≥65 years of age (average 435.1 / 1,000), and lowest for infants under 2 years of age (average 69.5 / 1,000). A summary of final pharmacy surveillance data will be included in the 2012-13 FluWatch annual report.
Note: Pharmacy sales data are provided to the Public Health Agency of Canada by Rx Canada Inc. and sourced from major retail drug chains representing over 3,000 stores nationwide (excluding Nunavut) in 85% of Health Regions. Data provided include the number of new antiviral prescriptions (for Tamiflu and Relenza) and the total number of new prescriptions dispensed by Province/Territory and age group.

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Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

In week 13, 19 new laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalizations were reported by the Immunization Monitoring Program Active (IMPACT) network, compared to 26 in week 12. Among the cases reported in week 13, 73.7% (14) were identified with influenza B and the rest were A(unsubtyped). For the fifth week in a row, the number of influenza B cases exceeded the number of influenza A cases, a reversal of the pattern seen earlier in the season. The age distribution is as follows: one (5.3%) between 0-5 months, 8 (42.1%) between 6-23 months, 4 (21.1%) 2-4 years of age, 4 (21.1%) 5-9 years of age, and 2 (10.5%) 10-16 years of age. Three admissions to intensive care unit (ICU) were reported during the week 13, one child 6-23 months of age (influenza type unknown); and one 2-4 years of age and one 10-16 years of age, both with influenza B.

Since the start of the 2012-13 season, a total of 755 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 611 (80.9%) with influenza A [of which 118 (19.3%) were A(H3N2), 22 (3.6%) were A(H1N1)pdm09 and the remaining 471 were A(unsubtyped); and 144 (19.1%) with influenza B. The distribution of cases by age group is as follows: 141 (18.7%) < 6 months of age; 186 (24.6%) age 6-23 months; 213 (28.2%) age 2-4 years; 151 (20.0%) age 5-9 years; and 64 (8.5%) age 6-10 years. Seventy-four (9.8%) of the 755 cases were admitted to the ICU. No deaths have been reported to date.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associate paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

In week 13, five laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations were reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network, compared to 14 in week 12. Two of the five hospitalizations were cases of influenza A(unsubtyped), two were influenza B and one was untyped. All five cases were ≥65 years of age. One ICU admission was reported during the current week, in a person ≥65 years of age with influenza B. One death was reported, also a case ≥65 years of age, with influenza A(unsubtyped).

From week 45 to week 13, 1,614 influenza-associated adult hospitalizations were reported by the PCIRN-SOS network: 1,498 (92.8%) with influenza A [of which 242 were A(H3N2), 13 were A(H1N1)pdm09, and 1,243 were A(unsubtyped)]; 62 (3.8%) with influenza B, and the type has not been reported for 54 cases. The age distribution of hospitalizations is as follows: 1,123 (69.6%) were ≥65 years of age, 315 (19.5%) were 45-64 years, 168 (10.4%) were 20-44 years, and 8 (0.5%) were <20 years of age. ICU admission was required for 176 hospitalizations; the majority of which were adults ≥65 years of age (111; 63.1%). Of the ICU admissions, 68 (38.6%) had at least one co-morbidity, three (1.7%) had no co-morbidities, and 105 had no information to date. A total of 93 deaths have been reported: 16 with influenza A(H3N2), 71 with influenza A(unsubtyped), 5 with influenza B, and one untyped. More than 80% of the deaths (78/93) were in adults ≥65 years of age, 12 (12.9%) were adults 45-64 years of age, and 3 (3.2%) were 20-44 years of age. Thirty-nine deaths occurred in individuals who had at least one co-morbidity. Detailed clinical information on co-morbidities is not known for the remaining cases.
Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associate adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)

In week 13, 83 laboratory-confirmed influenza-associated hospitalizations were reported from participating provinces and territories<SUP>*</SUP>. The majority of cases were influenza A (57; 68.7%). The highest proportion of hospitalisations were in adults ≥65 years of age (43.4%), followed by children 0-4 years of age (21.7%). Of the 20 cases with available data, four were admitted to the ICU: two children, one 0-4 and one 5-14 years of age; and two adults, one 20-44 and one 45-64 years of age. No deaths were reported in week 13. Data was not received for the Yukon Territories.

To date this season 4,126 influenza-associated hospitalizations have been reported, of which 93.5% have been influenza A. Of those subtyped (48.4%), influenza A(H3) was the predominant influenza strain. The cumulative proportion of hospitalizations with influenza B continues to increase (6.4% in week 13). Age information was available for 4,123 cases, and the age distribution is as follows: 2,272 (55.1%) were ≥65 years of age; 686 (16.6%) were 45-64 years of age; 368 (8.9%) were 20-44 years of age; 38 (0.9%) were 15-19 years of age; 172 (4.2%) were 5-14 years; and 587 (14.2%) were 0-4 years of age. Of the 1,105 cases with available data, there have been 175 hospitalisations for which admission to an ICU was required; the highest proportions are adults 45-64 years of age, followed by adults ≥65 years of age (36.6% and 34.3%, respectively). To date, 276 deaths have been reported: 229 were adults ≥65 years of age, 30 were adults 45-64 years; 11 were adults 20-44 years, one was a child 5-14 years of age, and 5 were children 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

.../
http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php

[Pathfinder]

Re: Canada FluWatch Weekly Reports 2012-2013 Season Week 11

FluWatch report: March 10 to March 16, 2013 (Week 11)

Posted 2013-03-22For readers interested in the <ABBR title="Portable Document Format">PDF</ABBR> version, the document is available for downloading or viewing:
<A title="Flu Watch (Version PDF, 113 KB - 6 pages)" href="http://www.phac-aspc.gc.ca/fluwatch/12-13/w11_13/pdf/fw2013-11-eng.pdf">FluWatch report: March 10 to March 16, 2013 (Week 11) (<ABBR title="Portable Document Format">PDF</ABBR> Version - 113 <ABBR title=Kilobytes>KB</ABBR> - 8 pages)

»» Help with PDF documents

Overall Summary

• Overall detections of influenza continued to decline, however the proportion of influenza B detections increased.
• The proportions of tests positive for other respiratory viruses increased.
• In week 11, 62% of paediatric hospitalizations were associated with influenza B.
• Several indicators, including the number of regions reporting widespread or localized activity, the ILI consultation rate, and the proportion of prescriptions for antivirals decreased in week 11.
• Similar to previous years, older adults (persons aged ≥65 years) are the most affected this season; with 45.0% of laboratory detections to date, 69.2% of adult hospitalizations reported through the PCIRN-SOS network, outbreaks in long-term care facilities, and the highest proportion of antiviral prescriptions.

Influenza Activity (geographic spread) and Outbreaks

In week 11, one region [in ON] reported widespread activity and 12 regions [in BC(1), AB(1), ON(6), QC(1), NS(2) and NL(1)] reported localized activity. The number of regions reporting widespread or localized activity decreased compared to the previous week and continued to follow the overall decline in influenza/ILI activity from the peak in early January (Figures 1 and 2). Twenty-four new influenza outbreaks were reported: 17 in long-term-care facilities, one in a hospital, one in a school, and five in other facilities or communities (Figure 3).
Figure 1. Map of overall Influenza activity level by province and territory,
Canada, Week 11





Note: Influenza activity levels, as represented on this map, are assigned and reported by Provincial and Territorial Ministries of Health, based on laboratory confirmations, sentinel ILI rates (see graphs and tables) and reported outbreaks. Please refer to detailed definitions on the last page. For areas where no data is reported, late reports from these provinces and territories will appear on the FluWatch website.
Text equivalent for figure 1Map of overall Influenza activity level by province and territory, Canada
Figure 2. Number of influenza surveillance regions<SUP title="sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in">†</SUP> reporting widespread or localized influenza activity, Canada, by report week, 2012-2013 (N<SUP>*</SUP>=58)


†sub-regions within the province or territory as defined by the provincial/territorial epidemiologist. Graph may change as late returns come in.
* Total number of influenza surveillance regions in Canada
Text equivalent for figure 2Number of influenza surveillance regions reporting widespread or localized influenza activity, Canada, by report week, 2011-2012 (N=56)
Figure 3. Overall Number of Influenza Outbreaks, Canada, by Report Week, 2012-2013


Text equivalent for figure 3Overall Number of Influenza Outbreaks, Canada, by Report Week, 2011-2012

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Influenza and Other Respiratory Virus Detections

The percentage of positive influenza tests decreased from 13.1% in week 10 to 12.2% in week 11 (Figure 4). Among the influenza viruses detected in week 10 (n=507), 55.4% were positive for influenza A viruses [of which 22.6% were A(H3), 20.8% were A(H1N1)pdm09, and 56.6% were A(unsubtyped)] (Table 1). The proportion of influenza B detections has increased over the past 8 weeks from 2.1% in week 03 to 55.4% in week 11 (Figure 4). Cumulative influenza virus detections by type/subtype to date are as follows: 93.0% influenza A [34.9% A(H3), 4.0% A(H1N1)pdm09 and 61.1% A(unsubtyped)] and 7.0% influenza B (Table 1).
Detailed information on age and type/subtype has been received for 22,036 cases to date this season (Table 2). ). The proportion of cases by age group is as follows: 13.7% < 5 years; 8.9% between 5-19 years; 15.6% between 20-44 years; 16.8% between 45-64 years of age; 45.0% ≥ 65 years.
The percentage of tests positive decreased for RSV, from 17.6% in week 10 to 15.4% in week 11. The percentage of positive tests increased for all other viruses: rhinovirus (9.4%), hMPV (5.2%), coronavirus (4.2%), parainfluenza (4.1%) and adenovirus (1.9%) (Figure 5)<SUP>*</SUP>.
* For more details, see the weekly Respiratory Virus Detections in Canada Report.
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION class=alignCenter>Table 1: Weekly & Cumulative numbers of positive influenza specimens
by Provincial Laboratories, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=ar1 rowSpan=3>Reporting provinces</TH><TH id=ac1 colSpan=6>Weekly
(March 10 to March 16, 2013)</TH><TH id=ac9 colSpan=6>Cumulative
(August 26, 2012 to March 16, 2013)</TH></TR><TR class=bg-colour-yellow><TH id=ac2 colSpan=5 headers=ac1>Influenza A</TH><TH id=ac8 headers=ac1>Influenza
B</TH><TH id=ac10 colSpan=5 headers=ac9>Influenza A</TH><TH id=ac16 headers=ac9>Influenza
B</TH></TR><TR class=bg-colour-yellow><TH id=ac3 headers=ac2>A Total</TH><TH id=ac4 headers=ac2>A(H1)</TH><TH id=ac5 headers=ac2>A(H3)</TH><TH id=ac6 headers=ac2>Pand H1N1</TH><TH id=ac7 class=noWrap headers=ac2>A
( <ABBR title=unsubtyped>Un S</ABBR>)Table 1 note*</TH><TH headers="ac1 ac8">Total</TH><TH id=ac11 headers=ac10>A Total</TH><TH id=ac12 headers=ac10>A(H1)</TH><TH id=ac13 headers=ac10>A(H3)</TH><TH id=ac14 headers=ac10>Pand H1N1</TH><TH id=ac15 class=noWrap headers=ac10>A
(Un S) Table 1 note*</TH><TH headers=ac16>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=13>* Unsubtyped: The specimen was typed as influenza A, but no result for subtyping was available. Specimens from NT, YT, and NU are sent to reference laboratories in other provinces. Note: Weekly data is based on week of positive lab detection. Cumulative data includes updates to previous weeks; due to reporting delays, the sum of weekly report totals do not add up to cumulative totals. </TD></TR></TFOOT><TBODY><TR><TH id=ar2 class=bg-colour-yellow headers=ar1><ABBR title="British Columbia ">BC</ABBR></TH><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac3">32</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac5">15</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac6">12</TD><TD class=alignRight headers="ar1 ar2 ac1 ac2 ac7">5</TD><TD class=alignRight headers="ar1 ar2 ac1 ac8">27</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac11">1872</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac13">1435</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac14">200</TD><TD class=alignRight headers="ar1 ar2 ac9 ac10 ac15">237</TD><TD class=alignRight headers="ar1 ar2 ac9 ac16">299</TD></TR><TR><TH id=ar3 class=bg-colour-yellow headers=ar1><ABBR title=Alberta>AB</ABBR></TH><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac3">21</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac5">8</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac6">10</TD><TD class=alignRight headers="ar1 ar3 ac1 ac2 ac7">3</TD><TD class=alignRight headers="ar1 ar3 ac1 ac8">47</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac11">2276</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac13">1741</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac14">391</TD><TD class=alignRight headers="ar1 ar3 ac9 ac10 ac15">144</TD><TD class=alignRight headers="ar1 ar3 ac9 ac16">370</TD></TR><TR><TH id=ar4 class=bg-colour-yellow headers=ar1><ABBR title=Saskatchewan>SK</ABBR></TH><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac3">16</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac5">6</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac6">8</TD><TD class=alignRight headers="ar1 ar4 ac1 ac2 ac7">2</TD><TD class=alignRight headers="ar1 ar4 ac1 ac8">15</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac11">809</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac13">474</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac14">59</TD><TD class=alignRight headers="ar1 ar4 ac9 ac10 ac15">276</TD><TD class=alignRight headers="ar1 ar4 ac9 ac16">128</TD></TR><TR><TH id=ar5 class=bg-colour-yellow headers=ar1><ABBR title=Manitoba>MB</ABBR></TH><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac3">7</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar5 ac1 ac2 ac7">7</TD><TD class=alignRight headers="ar1 ar5 ac1 ac8">3</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac11">611</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac13">78</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac14">8</TD><TD class=alignRight headers="ar1 ar5 ac9 ac10 ac15">525</TD><TD class=alignRight headers="ar1 ar5 ac9 ac16">50</TD></TR><TR><TH id=ar6 class=bg-colour-yellow headers=ar1><ABBR title=Ontario>ON</ABBR></TH><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac3">68</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac5">20</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac6">16</TD><TD class=alignRight headers="ar1 ar6 ac1 ac2 ac7">32</TD><TD class=alignRight headers="ar1 ar6 ac1 ac8">50</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac11">8070</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac13">3743</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac14">294</TD><TD class=alignRight headers="ar1 ar6 ac9 ac10 ac15">4033</TD><TD class=alignRight headers="ar1 ar6 ac9 ac16">391</TD></TR><TR><TH id=ar7 class=bg-colour-yellow headers=ar1><ABBR title=Quebec>QC</ABBR>
</TH><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac3">43</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac6">1</TD><TD class=alignRight headers="ar1 ar7 ac1 ac2 ac7">42</TD><TD class=alignRight headers="ar1 ar7 ac1 ac8">136</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac11">9671</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac13">546</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac14">30</TD><TD class=alignRight headers="ar1 ar7 ac9 ac10 ac15">9095</TD><TD class=alignRight headers="ar1 ar7 ac9 ac16">712</TD></TR><TR><TH id=ar8 class=bg-colour-yellow headers=ar1><ABBR title="New Brunswick">NB</ABBR>
</TH><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac3">9</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar8 ac1 ac2 ac7">9</TD><TD class=alignRight headers="ar1 ar8 ac1 ac8">1</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac11">1804</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac13">757</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac14">50</TD><TD class=alignRight headers="ar1 ar8 ac9 ac10 ac15">997</TD><TD class=alignRight headers="ar1 ar8 ac9 ac16">10</TD></TR><TR><TH id=ar9 class=bg-colour-yellow headers=ar1><ABBR title="Nova Scotia ">NS</ABBR>
</TH><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac3">23</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar9 ac1 ac2 ac7">23</TD><TD class=alignRight headers="ar1 ar9 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac11">335</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac13">165</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac14">5</TD><TD class=alignRight headers="ar1 ar9 ac9 ac10 ac15">165</TD><TD class=alignRight headers="ar1 ar9 ac9 ac16">3</TD></TR><TR><TH id=ar10 class=bg-colour-yellow headers=ar1><ABBR title="Prince Edward Island ">PE</ABBR>
</TH><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac3">2</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac5">2</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac2 ac7">0</TD><TD class=alignRight headers="ar1 ar10 ac1 ac8">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac11">104</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac13">73</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac14">3</TD><TD class=alignRight headers="ar1 ar10 ac9 ac10 ac15">28</TD><TD class=alignRight headers="ar1 ar10 ac9 ac16">1</TD></TR><TR><TH id=ar11 class=bg-colour-yellow headers=ar1><ABBR title="Newfoundland/Labrador ">NL</ABBR>
</TH><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac3">5</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac5">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac6">0</TD><TD class=alignRight headers="ar1 ar11 ac1 ac2 ac7">5</TD><TD class=alignRight headers="ar1 ar11 ac1 ac8">2</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac11">701</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac13">152</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac14">0</TD><TD class=alignRight headers="ar1 ar11 ac9 ac10 ac15">549</TD><TD class=alignRight headers="ar1 ar11 ac9 ac16">9</TD></TR><TR><TH id=ar12 class=bg-colour-yellow headers=ar1>Canada</TH><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac3">226</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac4">0</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac5">51</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac6">47</TD><TD class=alignRight headers="ar1 ar12 ac1 ac2 ac7">128</TD><TD class=alignRight headers="ar1 ar12 ac1 ac8">281</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac11">26253</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac12">0</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac13">9164</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac14">1040</TD><TD class=alignRight headers="ar1 ar12 ac9 ac10 ac15">16049</TD><TD class=alignRight headers="ar1 ar12 ac9 ac16">1973</TD></TR></TBODY></TABLE>
<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 2. Weekly & Cumulative numbers of positive influenza specimens by age groups
reported through case-based laboratory reporting, Canada, 2012-2013 Table 2 note*</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=br1 rowSpan=3>Age groups</TH><TH id=bc1 colSpan=5>Weekly
(March 10 to March 16, 2013)</TH><TH id=bc8 colSpan=5>Cumulative
(August 26, 2012 to March 16, 2013)</TH></TR><TR class=bg-colour-yellow><TH id=bc2 colSpan=4 headers=bc1>Influenza A</TH><TH id=bc7 headers=bc1>B</TH><TH id=bc9 colSpan=4 headers=bc8>Influenza A</TH><TH id=bc14 headers=bc8>B</TH></TR><TR class=bg-colour-yellow><TH id=bc3 headers=bc2>A Total</TH><TH id=bc4 headers=bc2>Pandemic H1N1</TH><TH id=bc5 headers=bc2>A/H3N2</TH><TH id=bc6 headers=bc2>A unsubtyped</TH><TH headers="bc1 bc7">Total</TH><TH id=bc10 headers=bc9>A Total</TH><TH id=bc11 headers=bc9>Pandemic H1N1</TH><TH id=bc12 headers=bc9>A/H3N2</TH><TH id=bc13 headers=bc9>A unsubtyped</TH><TH headers=bc14>Total</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=11>* Please note that this table reflects the number of specimens for which demographic information was reported. These represent a subset of all positive influenza cases reported. Delays in the reporting of data may cause data to change retrospectively. </TD></TR></TFOOT><TBODY><TR><TH id=br2 headers=br1><5</TH><TD class=alignRight headers="br1 br2 bc1 bc2 bc3">10</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc4">2</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br2 bc1 bc2 bc6">8</TD><TD class=alignRight headers="br1 br2 bc1 bc7">36</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc10">2669</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc11">188</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc12">926</TD><TD class=alignRight headers="br1 br2 bc8 bc9 bc13">1555</TD><TD class=alignRight headers="br1 br2 bc8 bc14">348</TD></TR><TR><TH id=br3 headers=br1>5-19</TH><TD class=alignRight headers="br1 br3 bc1 bc2 bc3">10</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc4">4</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br3 bc1 bc2 bc6">6</TD><TD class=alignRight headers="br1 br3 bc1 bc7">58</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc10">1470</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc11">69</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc12">669</TD><TD class=alignRight headers="br1 br3 bc8 bc9 bc13">732</TD><TD class=alignRight headers="br1 br3 bc8 bc14">499</TD></TR><TR><TH id=br4 headers=br1>20-44</TH><TD class=alignRight headers="br1 br4 bc1 bc2 bc3">19</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc4">6</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc5">3</TD><TD class=alignRight headers="br1 br4 bc1 bc2 bc6">10</TD><TD class=alignRight headers="br1 br4 bc1 bc7">26</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc10">3140</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc11">301</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc12">1268</TD><TD class=alignRight headers="br1 br4 bc8 bc9 bc13">1571</TD><TD class=alignRight headers="br1 br4 bc8 bc14">289</TD></TR><TR><TH id=br5 headers=br1>45-64</TH><TD class=alignRight headers="br1 br5 bc1 bc2 bc3">22</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc4">7</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc5">4</TD><TD class=alignRight headers="br1 br5 bc1 bc2 bc6">11</TD><TD class=alignRight headers="br1 br5 bc1 bc7">36</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc10">3439</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc11">284</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc12">1261</TD><TD class=alignRight headers="br1 br5 bc8 bc9 bc13">1894</TD><TD class=alignRight headers="br1 br5 bc8 bc14">272</TD></TR><TR><TH id=br6 headers=br1>65+</TH><TD class=alignRight headers="br1 br6 bc1 bc2 bc3">56</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc4">2</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc5">19</TD><TD class=alignRight headers="br1 br6 bc1 bc2 bc6">35</TD><TD class=alignRight headers="br1 br6 bc1 bc7">28</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc10">9617</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc11">98</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc12">3760</TD><TD class=alignRight headers="br1 br6 bc8 bc9 bc13">5759</TD><TD class=alignRight headers="br1 br6 bc8 bc14">293</TD></TR><TR><TH id=br7 headers=br1>Unknown</TH><TD class=alignRight headers="br1 br7 bc1 bc2 bc3">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc4">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc5">0</TD><TD class=alignRight headers="br1 br7 bc1 bc2 bc6">0</TD><TD class=alignRight headers="br1 br7 bc1 bc7">0</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc10">165</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc11">19</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc12">144</TD><TD class=alignRight headers="br1 br7 bc8 bc9 bc13">2</TD><TD class=alignRight headers="br1 br7 bc8 bc14">0</TD></TR><TR><TH id=br8 headers=br1>Total</TH><TD class=alignRight headers="br1 br8 bc1 bc2 bc3">117</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc4">21</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc5">26</TD><TD class=alignRight headers="br1 br8 bc1 bc2 bc6">70</TD><TD class=alignRight headers="br1 br8 bc1 bc7">184</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc10">20500</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc11">959</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc12">8028</TD><TD class=alignRight headers="br1 br8 bc8 bc9 bc13">11513</TD><TD class=alignRight headers="br1 br8 bc8 bc14">1701</TD></TR></TBODY></TABLE>


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Figure 4. Influenza tests reported and percentage of tests positive, Canada,
by report week, 2012-2013


Text equivalent for figure 4Influenza tests reported and percentage of tests positive, Canada, by report week, 2011-2012
Figure 5. Percent positive influenza tests, compared to other respiratory viruses,
Canada, by reporting week, 2012-2013


Text equivalent for figure 5Percent positive influenza tests, compared to other respiratory viruses, Canada, by reporting week, 2011-2012

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Influenza strain characterizations

During the 2012-13 season, the National Microbiology Laboratory (NML) has antigenically characterized 798 influenza viruses. The 470 influenza A(H3N2) viruses were antigenically similar to the vaccine strain A/Victoria/361/2011 and the 128 A(H1N1)pdm09 viruses were antigenically similar to the vaccine strain A/California/07/09. Among the influenza B viruses, 160 were antigenically similar to the vaccine strain B/Wisconsin/01/2010 (Yamagata lineage) and 40 were similar to B/Brisbane/60/2008 (Victoria lineage; component of the 2011-2012 seasonal influenza vaccine) (Figure 6).
Figure 6. Influenza strain characterizations, Canada, 2012-2013, N = 798

Note: The recommended components for the 2012-2013 Northern Hemisphere influenza vaccine include: an A/Victoria/361/2011 (H3N2)-like virus; an A/California/7/2009 (H1N1)pdm09-like virus; and a B/Wisconsin/1/2010-like virus.
Text equivalent for figure 6Influenza strain characterizations, Canada, 2011-2012

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Antiviral resistance

During the 2012-13 season, NML has tested 730 influenza viruses for resistance to oseltamivir, and 727 influenza viruses for resistance to zanamivir. All viruses tested were sensitive to oseltamivir and zanamivir. A total of 886 influenza A viruses were tested for amantadine resistance and all were resistant (Table 3).


<TABLE class=widthFull border=1 cellSpacing=0 cellPadding=2><CAPTION>Table 3. Antiviral resistance by influenza virus type and subtype, Canada, 2012-2013</CAPTION><THEAD><TR class=bg-colour-yellow><TH id=cr1 rowSpan=2>Virus type and subtype</TH><TH id=cc1 colSpan=2>Oseltamivir</TH><TH id=cc4 colSpan=2>Zanamivir</TH><TH id=cc7 colSpan=2>Amantadine</TH></TR><TR class=bg-colour-yellow><TH id=cc2 headers=cc1># tested</TH><TH id=cc3 headers=cc1># resistant (%)</TH><TH id=cc5 headers=cc4># tested</TH><TH id=cc6 headers=cc4># resistant (%)</TH><TH id=cc8 headers=cc7># tested</TH><TH id=cc9 headers=cc7># resistant (%)</TH></TR></THEAD><TFOOT><TR><TD class=fontSize85 colSpan=7><SUP>*</SUP> NA - not applicable</TD></TR></TFOOT><TBODY><TR><TH id=cr2 class="alignLeft bg-colour-blue" headers=cr1>A (H3N2)</TH><TD class=alignCenter headers="cr2 cc2">462</TD><TD class=alignCenter headers="cr2 cc3">0</TD><TD class=alignCenter headers="cr2 cc5">461</TD><TD class=alignCenter headers="cr2 cc6">0</TD><TD class=alignCenter headers="cr2 cc8">772</TD><TD class=alignCenter headers="cr2 cc9">772 (100%)</TD></TR><TR><TH id=cr3 class="alignLeft bg-colour-blue" headers=cr1>A (H1N1)</TH><TD class=alignCenter headers="cr3 cc2">106</TD><TD class=alignCenter headers="cr3 cc3">0</TD><TD class=alignCenter headers="cr3 cc5">104</TD><TD class=alignCenter headers="cr3 cc6">0</TD><TD class=alignCenter headers="cr3 cc8">114</TD><TD class=alignCenter headers="cr3 cc9">114</TD></TR><TR><TH id=cr4 class="alignLeft bg-colour-blue" headers=cr1>B</TH><TD class=alignCenter headers="cr4 cc2">162</TD><TD class=alignCenter headers="cr4 cc3">0</TD><TD class=alignCenter headers="cr4 cc5">162</TD><TD class=alignCenter headers="cr4 cc6">0</TD><TD class=alignCenter headers="cr4 cc8">NA <SUP>*</SUP></TD><TD class=alignCenter headers="cr4 cc9">NA <SUP>*</SUP></TD></TR><TR><TH id=cr5 class="alignLeft bg-colour-blue" headers=cr1>TOTAL</TH><TD class=alignCenter headers="cr5 cc2">730</TD><TD class=alignCenter headers="cr5 cc3">0</TD><TD class=alignCenter headers="cr5 cc5">727</TD><TD class=alignCenter headers="cr5 cc6">0</TD><TD class=alignCenter headers="cr5 cc8">886</TD><TD class=alignCenter headers="cr5 cc9">886 (100%)</TD></TR></TBODY></TABLE>
Influenza-like Illness (ILI) Consultation Rate

The national influenza-like-illness (ILI) consultation rate decreased from 26.5 ILI consultations per 1,000 patient visits in week 10, to 23.2 in week 11 and is within the expected range (Figure 7). In week 11, the highest consultation rate was observed in children less than 5 years of age (68.6/1,000).
Figure 7. Influenza-like illness (ILI) consultation rates, Canada, by report week, 2012-2013 compared to 1996/97 through to 2011/12 seasons (with pandemic data suppressed)



Note: No data available for mean rate in previous years for weeks 19 to 39 (1996-1997 through 2002-2003 seasons). Delays in the reporting of data may cause data to change retrospectively.
Text equivalent for figure 7Influenza-like illness (ILI) consultation rates, Canada, by report week, 2011-2012 compared to 1996/97 through to 2010/11 seasons (with pandemic data suppressed)
Pharmacy Surveillance

The Canadian antiviral prescription rate decreased from 93.5 antiviral prescriptions per 100,000 new prescriptions dispensed in week 10 to 47.2/100,000 in week 11; a rate similar to that observed at the end of November 2012 (week 47). The antiviral prescription rate decreased for children, adults and seniors, and was stable for infants, but this rate was the lowest of all age-groups at 11.7/100,000. The highest rate continued to be observed for seniors ≥65 years of age at 94.7/100,000.
Note: Pharmacy sales data are provided to the Public Health Agency of Canada by Rx Canada Inc. and sourced from major retail drug chains representing over 3,000 stores nationwide (excluding Nunavut) in 85% of Health Regions. Data provided include the number of new antiviral prescriptions (for Tamiflu and Relenza) and the total number of new prescriptions dispensed by Province/Territory and age group.
Severe Respiratory Illness Surveillance

Paediatric Influenza Hospitalizations and Deaths (IMPACT)

In week 11, 21 new laboratory-confirmed influenza-associated paediatric (≤16 years of age) hospitalizations were reported by the Immunization Monitoring Program Active (IMPACT) network, compared to 22 in week 10. Among the cases reported in week 11, 62% (13) were identified with influenza B, 14% (3) with A(H1N1)pdm09 and 24% (5) with A(unsubtyped). For the third week in a row, the number of influenza B cases exceeded the number of influenza A cases, a reversal of the pattern seen earlier in the season. The age distribution is as follows: 2 cases (9.5%) under 6 months of age, 7 (33.3%) between 6-23 months, 3 (14.3%) 2-4 years of age, 7 (33.3%) 5-9 years of age, and 2 (9.5%) 10-16 years of age. One admission to an Intensive Care Unit (ICU) was reported during week 11, a child 2-4 years of age with influenza B.

Since the start of the 2012-13 season, a total of 713 influenza-associated paediatric hospitalizations have been reported by the IMPACT network: 605 (84.9%) with influenza A [of which 112 (18.5%) were A(H3N2), 19 (3.1%) were A(H1N1)pdm09 and the remaining 474 were A(unsubtyped)]; and 108 (15.1%) with influenza B. The distribution of cases by age group is as follows: 140 (19.6%) <6 months of age; 169 (23.7%) age 6-23 months; 208 (29.2%) age 2-4 years; 135 (18.9%) age 5-9 years; and 61 (8.6%) age 10-16 years. Sixty-one of the 713 cases (8.6%) were admitted to the ICU. No deaths have been reported to date.

Note: The number of hospitalizations reported through IMPACT represents a subset of all influenza-associate paediatric hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Adult Influenza Hospitalizations and Deaths (PCIRN)

In week 11, 21 new laboratory-confirmed influenza-associated adult (≥16 years of age) hospitalizations were reported by the PHAC/CIHR Influenza Research Network (PCIRN) Serious Outcomes Surveillance (SOS) network. Ninety-one percent (19) of the hospitalizations were cases of influenza A. Fourteen cases were ≥65 years of age, six were 45-64 years of age, and one was 20-44 years of age. One ICU admission was reported during the current week, in a person ≥65 years of age with influenza A(unsubtyped). Three deaths were reported: all three with influenza A(unsubtyped), two ≥65 years and one 20-44 years of age.

From week 45 to week 11, 1,538 influenza-associated adult hospitalizations have been reported by the PCIRN-SOS network: 1,441 (93.7%) with influenza A [of which 206 were A(H3N2), 12 were A(H1N1)pdm09, and 1,223 were A(unsubtyped)]; 52 (3.4%) with influenza B, and the type has not been reported for 45 cases. The age distribution of hospitalizations is as follows: 1064 (69.2%) were ≥65 years of age, 305 (19.8%) were 45-64 years, 161 (10.5%) were 20-44 years, and 8 (0.5%) were <20 years of age. ICU admission was required for 161 hospitalizations; the majority of which were adults ≥65 years of age (100; 62.1%). Of the ICU admissions, 60 (37.3%) had at least one co-morbidity, two (1.2%) had no co-morbidities, and 99 had no information to date. A total of 87 deaths have been reported: 15 with influenza A(H3N2), 67 with influenza A(unsubtyped), 4 with influenza B, and one untyped. More than 80% of the deaths (73/87) were in adults ≥65 years of age, 11 (12.6%) were adults 45-64 years of age, and 3 (3.4%) were 20-44 years of age.

Thirty-six deaths occurred in individuals who had at least one co-morbidity. Detailed clinical information on co-morbidities is not known for the remaining cases.

Note: The number of hospitalizations reported through PCIRN represents a subset of all influenza-associate adult hospitalizations in Canada. Delays in the reporting of data may cause data to change retrospectively.

Provincial/Territorial Influenza Hospitalizations and Deaths (Aggregate Surveillance System<SUP>*</SUP>)

In week 11, 95 laboratory-confirmed influenza-associated hospitalizations were reported from participating provinces and territories<SUP>*</SUP>. The majority of cases were influenza A (61; 64.2%), predominantly A(H3). The highest proportion of hospitalisations continued to be adults ≥65 years of age (40.0%), followed by children 0-4 years of age (25.3%). Of the 37 cases with available data, seven were admitted to the ICU - one child aged 0-4 years; one aged 5-14 years; three adults aged 45-64 years; and two aged ≥65 years. Two deaths were reported: both adults aged ≥65 years; one influenza B and one A(H3). It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases. Data were not received for the Yukon Territories in week 11.

To date this season 3,944 influenza-associated hospitalizations have been reported; of which 95.0% have been influenza A, predominantly A(H3). The cumulative proportion of hospitalizations in cases with influenza B has increased from 1.6% in week 01, to 5.0% in week 11; which follows the trend of influenza B detections in Canada this season. Age information was available for 3,941 cases, and the age distribution is as follows: 2,190 (55.6%) were ≥65 years; 663 (16.8%) 45-64 years; 350 (8.9%) 20-44 years; 37 (0.9%) 15-19 years; 152 (3.9%) 5-14 years and 549 (13.9%) 0-4 years of age. Among the 1,052 cases with available data, there have been 168 (16.0%) hospitalisations for which admission to an ICU was required; the highest proportions being adults between 45-64 years of age and ≥65 years of age (36.9% and 35.1% respectively). To date, 271 deaths have been reported: 225 (83.0%) were adults ≥65 years of age, 29 (10.7%) were adults between 45-64 years of age; 11 (4.1%) were adults between 20-44 years of age, one child between 5-14 years of age and 5 (1.9%) between 0-4 years of age. It is important to note that the cause of death does not have to be attributable to influenza, a positive laboratory test is sufficient for reporting. Detailed clinical information (e.g. underlying medical conditions) is not known for these cases.

* Note: The number of new influenza-associated hospitalizations and deaths reported by the Aggregate Surveillance System each week may be overestimated, as it may include retrospective updates to data from Ontario for previous weeks. These data may also include cases reported by the IMPACT and PCIRN networks. Influenza-associated hospitalizations are not reported to PHAC by the following Provinces and Territory: BC, NU, QC, NS, and NB. Only hospitalizations that require intensive medical care are reported by Saskatchewan. ICU admissions are not reported in Ontario.

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http://www.phac-aspc.gc.ca/fluwatch/.../index-eng.php