hornblower
Moderator
(charts & tables at link)
http://www.phac-aspc.gc.ca/fluwatch/08-09/w26_09/index-eng.php
Summary of FluWatch Findings for the
Week ending July 8, 2009
The overall influenza activity level remain high for this time of the year, but has been decreasing in week 26, for the third consecutive week.
As of 8 July, 2009, all provinces and territories reported a total of 9,414 laboratory-confirmed cases of Pandemic (H1N1) 2009 including 878 hospitalizations and 37 deaths to the Public Health Agency of Canada (PHAC). While transmission continues to increase, the majority of illness has been mild thus far.
There was almost a 25% increase in the reported number of hospitalized Pandemic (H1N1) 2009 cases this week. Based on a proportion of hospitalized cases for whom the information was provided, 80% of the cases had one or more underlying medical conditions. Since July 3, 2009, eight deaths, one in Alberta, one in Saskatchewan, one in Manitoba, three in Ontario and two in Quebec were reported this week.
On July 5, 2009, a new reassortant influenza virus has been identified in 2 seasonal hog farm workers from Saskatchewan. The reassortant influenza virus is comprised of genes derived from the North American triple reassortant swine influenza A virus, first identified in Canada in 2005, and the current seasonal human H1N1 virus. This reassortment has never been identified before.
Pandemic (H1N1) 2009 virus Surveillance and Epidemiology
As of 8 July, 2009, all provinces and territories have reported a total of 9,414 laboratory-confirmed cases of Pandemic H1N1 2009 virus, of which 878 H1N1 cases were admitted to hospital. Cases were distributed similarly between males and females (52% for females, 47.8% for males, 0.2% unknown). One-hundred and fifty-one cases have been identified as First-Nations (139 cases in MB and 12 cases in BC) and 372 cases are from Nunavut, an area with a predominant Inuit population.
Core data was available for 721 (82.1%) hospitalizations. The median age of hospitalized cases was 19.5 years range (range <1 to 97 years). 129 (17.9%) of the hospitalized cases were reported to have been admitted to the intensive care unit (ICU). Information on underlying conditions was available from 291 cases of which 80.4% had one or more underlying medical condition: chronic heart disease (49 cases), diabetes (68 cases), kidney disease (23 cases), immuno-suppression (50 cases), lung disease (131 cases). Fourteen women were pregnant while infected.
Overall Influenza Summary
During week 26, ILI consultations rates (29 consultations per 1,000 visits) and proportion of influenza positive tests (16.0%) are still higher than expected for this time of the year, but are decreasing compared to the previous weeks.
Five regions in AB, SK, ON & NF reported localized activity, 36 regions sporadic activity in BC, AB, SK, MB, ON, QC, NB, NS, PEI & NT and 10 regions in NB, NS, NL, YK & NT reported no activity (no report received from NU). Two new influenza outbreaks were reported this week in hospitals (1 in AB, 1 in NL). Despite few reports of localized activity, no influenza outbreak was reported in Long-term care facilities.
ILI consultation rate
This week, the ILI consultation rate was 29 consultations per 1,000 patient visits (see ILI graph) which represents a slight decrease relative to the three previous weeks. The sentinel response rate was 75%.
Paediatric Influenza Hospitalizations and deaths
In week 26, nineteen laboratory-confirmed influenza-associated paediatric hospitalizations were reported through the Immunization Monitoring Program Active (IMPACT) network. To date this season, 690 hospitalizations have been reported; 227 (32.9%) of hospitalizations have been due to Pandemic (H1N1) 2009. The proportion of cases to date by age group are as follows: 13.5% were 0-5 month olds; 25.7% were 6-23 month olds; 21.9% were 2-4 year olds; 18.8% were 5-9 year olds; and 20.1% were 10-16 year olds. 54.2% of children between 5-16 years old are affected by Pandemic (H1N1) 2009 compared to 38.9% of same age children with seasonal influenza.
Laboratory Surveillance Summary
This week, the proportion of tests that were positive for influenza was 16.0% which is decreasing compared to previous weeks (see table). The majority (81.3%) of influenza virus detections this season have been for influenza A. 99.7% of influenza virus detections this week have been for influenza A likely due to the H1N1 flu virus.
Antigenic Characterization
As of 9 July, 2009, the NML tested 679 specimens for influenza H1N1 Flu Virus and 380 were positive. Positive samples were from AB, SK, MB, ON, QC, NB, NS, PEI and NL. *Provincial labs are also doing their own confirmation using RT-PCR.
On July 5, 2009, the Saskatchewan health authorities were informed by the National Microbiology Laboratory that a new reassortant influenza virus has been confirmed in 2 seasonal hog farm workers.Both worked for the same swine operation. The workers had mild illness around mid-June and were tested on June 18, 2009. Both have recovered since and are back to work. Mild respiratory illness has been detected in less than 1% of the affected herd. Results of swab testing from the animals are pending. The affected farm is part of a large operation which operates as a closed system. The reassortant influenza virus is comprised of genes derived from the North American triple reassortant swine influenza A virus, first identified in 2005, and the current seasonal human H1N1 virus. This reassortment has never been identified before.
Antiviral Resistance (from NML)
Oseltamivir: 303/304 seasonal A/H1N1 isolates were resistant (99.7%). Zanamivir: All seasonal A/H1N1 isolates tested were sensitive (0%). Adamantanes: 305/305 seasonal A/H3N2 isolates were resistant to amantadine (100%).
All Pandemic H1N1 2009 viruses tested so far have been sensitive to oseltamivir (208 samples) and zanamivir (91 samples) but resistant to amantadine (208 samples).
http://www.phac-aspc.gc.ca/fluwatch/08-09/w26_09/index-eng.php
Summary of FluWatch Findings for the
Week ending July 8, 2009
The overall influenza activity level remain high for this time of the year, but has been decreasing in week 26, for the third consecutive week.
As of 8 July, 2009, all provinces and territories reported a total of 9,414 laboratory-confirmed cases of Pandemic (H1N1) 2009 including 878 hospitalizations and 37 deaths to the Public Health Agency of Canada (PHAC). While transmission continues to increase, the majority of illness has been mild thus far.
There was almost a 25% increase in the reported number of hospitalized Pandemic (H1N1) 2009 cases this week. Based on a proportion of hospitalized cases for whom the information was provided, 80% of the cases had one or more underlying medical conditions. Since July 3, 2009, eight deaths, one in Alberta, one in Saskatchewan, one in Manitoba, three in Ontario and two in Quebec were reported this week.
On July 5, 2009, a new reassortant influenza virus has been identified in 2 seasonal hog farm workers from Saskatchewan. The reassortant influenza virus is comprised of genes derived from the North American triple reassortant swine influenza A virus, first identified in Canada in 2005, and the current seasonal human H1N1 virus. This reassortment has never been identified before.
Pandemic (H1N1) 2009 virus Surveillance and Epidemiology
As of 8 July, 2009, all provinces and territories have reported a total of 9,414 laboratory-confirmed cases of Pandemic H1N1 2009 virus, of which 878 H1N1 cases were admitted to hospital. Cases were distributed similarly between males and females (52% for females, 47.8% for males, 0.2% unknown). One-hundred and fifty-one cases have been identified as First-Nations (139 cases in MB and 12 cases in BC) and 372 cases are from Nunavut, an area with a predominant Inuit population.
Core data was available for 721 (82.1%) hospitalizations. The median age of hospitalized cases was 19.5 years range (range <1 to 97 years). 129 (17.9%) of the hospitalized cases were reported to have been admitted to the intensive care unit (ICU). Information on underlying conditions was available from 291 cases of which 80.4% had one or more underlying medical condition: chronic heart disease (49 cases), diabetes (68 cases), kidney disease (23 cases), immuno-suppression (50 cases), lung disease (131 cases). Fourteen women were pregnant while infected.
Overall Influenza Summary
During week 26, ILI consultations rates (29 consultations per 1,000 visits) and proportion of influenza positive tests (16.0%) are still higher than expected for this time of the year, but are decreasing compared to the previous weeks.
Five regions in AB, SK, ON & NF reported localized activity, 36 regions sporadic activity in BC, AB, SK, MB, ON, QC, NB, NS, PEI & NT and 10 regions in NB, NS, NL, YK & NT reported no activity (no report received from NU). Two new influenza outbreaks were reported this week in hospitals (1 in AB, 1 in NL). Despite few reports of localized activity, no influenza outbreak was reported in Long-term care facilities.
ILI consultation rate
This week, the ILI consultation rate was 29 consultations per 1,000 patient visits (see ILI graph) which represents a slight decrease relative to the three previous weeks. The sentinel response rate was 75%.
Paediatric Influenza Hospitalizations and deaths
In week 26, nineteen laboratory-confirmed influenza-associated paediatric hospitalizations were reported through the Immunization Monitoring Program Active (IMPACT) network. To date this season, 690 hospitalizations have been reported; 227 (32.9%) of hospitalizations have been due to Pandemic (H1N1) 2009. The proportion of cases to date by age group are as follows: 13.5% were 0-5 month olds; 25.7% were 6-23 month olds; 21.9% were 2-4 year olds; 18.8% were 5-9 year olds; and 20.1% were 10-16 year olds. 54.2% of children between 5-16 years old are affected by Pandemic (H1N1) 2009 compared to 38.9% of same age children with seasonal influenza.
Laboratory Surveillance Summary
This week, the proportion of tests that were positive for influenza was 16.0% which is decreasing compared to previous weeks (see table). The majority (81.3%) of influenza virus detections this season have been for influenza A. 99.7% of influenza virus detections this week have been for influenza A likely due to the H1N1 flu virus.
Antigenic Characterization
As of 9 July, 2009, the NML tested 679 specimens for influenza H1N1 Flu Virus and 380 were positive. Positive samples were from AB, SK, MB, ON, QC, NB, NS, PEI and NL. *Provincial labs are also doing their own confirmation using RT-PCR.
On July 5, 2009, the Saskatchewan health authorities were informed by the National Microbiology Laboratory that a new reassortant influenza virus has been confirmed in 2 seasonal hog farm workers.Both worked for the same swine operation. The workers had mild illness around mid-June and were tested on June 18, 2009. Both have recovered since and are back to work. Mild respiratory illness has been detected in less than 1% of the affected herd. Results of swab testing from the animals are pending. The affected farm is part of a large operation which operates as a closed system. The reassortant influenza virus is comprised of genes derived from the North American triple reassortant swine influenza A virus, first identified in 2005, and the current seasonal human H1N1 virus. This reassortment has never been identified before.
Antiviral Resistance (from NML)
Oseltamivir: 303/304 seasonal A/H1N1 isolates were resistant (99.7%). Zanamivir: All seasonal A/H1N1 isolates tested were sensitive (0%). Adamantanes: 305/305 seasonal A/H3N2 isolates were resistant to amantadine (100%).
All Pandemic H1N1 2009 viruses tested so far have been sensitive to oseltamivir (208 samples) and zanamivir (91 samples) but resistant to amantadine (208 samples).