FluView 2010-2011: Weeks 40-39

[Ronan Kelly]

http://www.cdc.gov/flu/weekly/

Exerpts

Synopsis:
Influenza A (H3N2), 2009 influenza A (H1N1), and influenza B viruses co-circulated at low levels in the United States during the summer months. During week 40 (October 3-9, 2010), influenza activity was low in the U.S.

?Forty-five (3.3%) specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division were positive for influenza.
?The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
?No influenza-associated pediatric deaths were reported.
?The proportion of outpatient visits for influenza-like illness (ILI) was below the national baseline. All 10 regions reported ILI below region-specific baseline levels and all 48 states with sufficient data experienced minimal ILI activity.
?Geographic spread of influenza in the District of Columbia, Guam, Puerto Rico, and 19 states was assessed as sporadic, 31 states reported no influenza activity and the U.S. Virgin Islands did not report.
------

5 H3, 4 A/H1N1, 22 A, 14 B. from 1368 tests.
7 hospitalizations and 1 death reported, (although most districts did not report)

-------

Antigenic Characterization:
A small number of isolates collected in the United States were available for antigenic characterization during the summer. CDC antigenically characterized 63 isolates collected from May 23 ? September 30, 2010, including 23 2009 influenza A (H1N1), 24 influenza A (H3N2), and 16 influenza B viruses.

Twenty-two of 23 (95.7%) 2009 influenza A (H1N1) viruses tested were closely related antigenically to the influenza A (H1N1) component of the 2010-11 influenza vaccine (A/California/7/2009-like); 22 of 24 (91.7%) influenza A (H3N2) viruses tested were closely related antigenically to the influenza A (H3N2) component of the vaccine (A/Perth/16/2009-like).

Influenza B viruses currently circulating globally can be divided into two distinct lineages represented by the B/Yamagata/16/88 and B/Victoria/02/87 viruses. Twelve of 16 (75%) influenza B viruses tested belonged to Victoria-lineage and were closely related antigenically to the influenza B component of the 2010-11 influenza vaccine (B/Brisbane/60/2008-like). Four of 16 (25%) influenza B viruses tested belonged to the Yamagata-lineage.

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[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-41

Re: FluView 2010-2011: Weeks 40-41

During week 41 (October 10-16, 2010), influenza activity remained low in the United States.

* Ninety-two (3.6%) specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division were positive for influenza.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
* No influenza-associated pediatric deaths were reported.
* The proportion of outpatient visits for influenza-like illness (ILI) was below the national baseline. All 10 regions reported ILI below region-specific baseline levels and all 49 states with sufficient data experienced minimal ILI activity.
* Geographic spread of influenza in the District of Columbia, Puerto Rico, and 24 states was assessed as sporadic, Guam and 26 states reported no influenza activity and the U.S. Virgin Islands did not report.

During week 41, 6.5% of all deaths reported through the 122-Cities Mortality Reporting System were due to P&I. This percentage was below the epidemic threshold of 6.6% for week 41.

Nationwide during week 41, 1.4% of patient visits reported through the U.S. Outpatient Influenza-like Illness Surveillance Network (ILINet) were due to influenza-like illness (ILI). This percentage is below the national baseline of 2.5%.
http://www.cdc.gov/flu/weekly/

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-42

Re: FluView 2010-2011: Weeks 40-42

During week 42 (October 17-23, 2010), influenza activity remained low in the United States.

* Forty-eight (3.0%) specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division were positive for influenza.
* The proportion of deaths attributed to pneumonia and influenza (6.4%) was below the epidemic threshold.
* No influenza-associated pediatric deaths were reported.
* The proportion of outpatient visits for influenza-like illness (ILI) was below the national baseline. All 10 regions reported ILI below region-specific baseline levels, and all 50 states experienced minimal ILI activity.
* Geographic spread of influenza in Guam and the U.S. Virgin Islands was assessed as regional; two states reported local influenza activity (TX,HI); the District of Columbia and 22 states were assessed as sporadic; 26 states reported no influenza activity, and Puerto Rico did not report.
http://www.cdc.gov/flu/weekly/

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-43

Re: FluView 2010-2011: Weeks 40-43

During week 43 (October 24-30, 2010), influenza activity remained low in the United States.

* Twenty-five (1.4%) specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division were positive for influenza.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
* One influenza-associated pediatric death was reported. This death was associated with an influenza A virus for which the subtype was undetermined and occurred during the 2009-10 season.
* The proportion of outpatient visits for influenza-like illness (ILI) was below the national baseline. All 10 regions reported ILI below region-specific baseline levels; one state experienced low ILI activity, 48 states experienced minimal ILI activity, and one state had insufficient data.
* Geographic spread of influenza in the U.S. Virgin Islands was reported as regional; Guam and one state reported local influenza activity; the District of Columbia, Puerto Rico, and 28 states reported sporadic activity; and 21 states reported no influenza activity.

CDC has antigenically characterized one 2009 influenza A (H1N1) and one influenza B collected by U.S. laboratories since October 1, 2010.
2009 Influenza A (H1N1) [1]
* This virus was characterized as A/California/7/2009-like, the 2009 influenza A (H1N1) component of the 2010-11 influenza vaccine for the Northern Hemisphere.

Influenza B [1]
* This virus belongs to the B/Victoria lineage of viruses and was characterized as B/Brisbane/60/2008-like, the recommended influenza B component for the 2010-11 Northern Hemisphere influenza vaccine.
http://www.cdc.gov/flu/weekly/

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-43

Re: FluView 2010-2011: Weeks 40-43

The percentage of specimens testing positive for influenza identified so far in the United States is low. The largest numbers of respiratory specimens testing positive for influenza have been reported in Regions 4 (AL, FL, GA, KY, MS, NC, SC, TN) and 9 (AZ, CA, HI, NV).
http://www.cdc.gov/flu/weekly/summary.htm

International co-circulation map (week 40-41)
http://www.cdc.gov/flu/international/map.htm

 

[Gert van der Hoek]

Re: FluView 2010-2011: Weeks 40-43

Re: FluView 2010-2011: Weeks 40-43

* One influenza-associated pediatric death was reported. This death was associated with an influenza A virus for which the subtype was undetermined and occurred during the 2009-10 season.

"the subtype was undetermined"

 

[sharon sanders]

Re: FluView 2010-2011: Weeks 40-43

Re: FluView 2010-2011: Weeks 40-43

"the subtype was undetermined"

I agree.

Thank you Missouriwatcher for your diligence in posting all these reports with analysis for the US, as a whole, and for state by state.

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-44

Re: FluView 2010-2011: Weeks 40-44

During week 44 (October 31-November 6, 2010), influenza activity remained low in the United States.

* Of 2,704 specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division, 185 (6.8%) were positive for influenza.
* Two human infections with novel influenza A viruses were reported.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
* One influenza-associated pediatric death was reported and was associated with an influenza A virus for which the subtype was undetermined.
* The proportion of outpatient visits for influenza-like illness (ILI), 1.3%, was below the national baseline, 2.5%. All 10 regions reported ILI below region-specific baseline levels; one state experienced low ILI activity, 49 states experienced minimal ILI activity.
* Geographic spread of influenza in three states was reported as local; the District of Columbia, Puerto Rico, and 34 states reported sporadic activity; Guam and 13 states reported no influenza activity, and the U.S. Virgin Islands did not report.

Two cases of human infection with a novel influenza A virus were reported: one case by the Wisconsin Department of Health Services and one case by the Pennsylvania Department of Health. Both patients were infected with a swine origin influenza A (H3N2) virus similar to the three other swine origin influenza A (H3N2) viruses previously identified in 2009 and 2010. The Wisconsin case reported contact with pigs in the week preceding symptom onset on September 8, 2010 and required hospitalization. No contact with pigs has been identified in the Pennsylvania case in the week before symptom onset on October 24, 2010; however the case lives in an area close to pig farms. Both patients have fully recovered from their illness. The cases are not related and the viruses from these two cases have some genetic differences, indicating that they did not come from the same source.

Although both investigations are ongoing, there is no evidence of human-to-human transmission with this virus in either case. Early identification and investigation of human infections with novel influenza A viruses is critical to evaluate the extent of the outbreak and possible human-to-human transmission. Surveillance for human infections with novel influenza A viruses continues year round.

CDC has antigenically characterized eight influenza viruses [four 2009 influenza A (H1N1) viruses, three influenza A (H3N2) viruses, and one influenza B virus] collected by U.S. laboratories since October 1, 2010.
2009 Influenza A (H1N1) [4]
* All four were characterized as A/California/7/2009-like, the influenza A (H1N1) component of the 2010-11 influenza vaccine for the Northern Hemisphere.
Influenza A (H3N2) [3]
* All three were characterized as A/Perth/16/2009-like, the influenza A (H3N2) component of the 2010-11 influenza vaccine for the Northern Hemisphere.
Influenza B [1]
* This virus belongs to the B/Victoria lineage of viruses and was characterized as B/Brisbane/60/2008-like, the recommended influenza B component for the 2010-11 Northern Hemisphere influenza vaccine.
http://www.cdc.gov/flu/weekly/

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-45

Re: FluView 2010-2011: Weeks 40-45

During week 45 (November 7-13, 2010), influenza activity remained low in the United States.

* Of 2,876 specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division, 220 (7.7%) were positive for influenza.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was at the epidemic threshold.
* No influenza-associated pediatric deaths were reported.
* The proportion of outpatient visits for influenza-like illness (ILI) was 1.3%, which is below the national baseline of 2.5%. All 10 regions reported ILI below region-specific baseline levels; one state experienced moderate ILI activity; one state experienced low ILI activity, and 48 states experienced minimal ILI activity.
* Geographic spread of influenza in Puerto Rico and four states was reported as local; the District of Columbia and 34 states reported sporadic activity; Guam and 12 states reported no influenza activity, and the U.S. Virgin Islands did not report.
http://www.cdc.gov/flu/weekly/

 

[sharon sanders]

Re: FluView 2010-2011: Weeks 40-45

Re: FluView 2010-2011: Weeks 40-45

* The proportion of deaths attributed to pneumonia and influenza (P&I) was at the epidemic threshold.

What does this mean if the overall influenza activity was low? A high number of pneumonia cases?

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-45

Re: FluView 2010-2011: Weeks 40-45

"Data collected in ILINet may disproportionately represent certain populations within a state, and therefore, may not accurately depict the full picture of influenza activity for the whole state."

I recall last year during peak of influenza, ILI graph was showing below baseline when P&I was above epidemic proportion. CDC has "corrected" the graph to show ILI over baseline during peak.

Distribute "Age-Stratified Heat Maps are plots of counts of Influenza like illness (ILI) over time, for each site, stratified by age group. The color represents the magnitude of the counts..." It seems that things are starting to "heat" up.
http://isds.cirg.washington.edu/distribute/ili.php

 

[sharon sanders]

Re: FluView 2010-2011: Weeks 40-45

Re: FluView 2010-2011: Weeks 40-45

Thanks Missouriwatcher!

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-46

Re: FluView 2010-2011: Weeks 40-46

Week 46:
* Of 2,876 specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division, 220 (7.7%) were positive for influenza.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
* No influenza-associated pediatric deaths were reported.
* The proportion of outpatient visits for influenza-like illness (ILI) was 1.4%, which is below the national baseline of 2.5%. All 10 regions reported ILI below region-specific baseline levels; one state experienced high ILI activity (Georgia); two states experienced low ILI activity, and 47 states experienced minimal ILI activity.
* The geographic spread of influenza in one state was reported as regional, Puerto Rico and seven states reported local activity; the District of Columbia, Guam, the U.S. Virgin Islands, and 31 states reported sporadic activity; and 11 states reported no influenza activity.

One death, associated with an influenza A virus for which the subtype was not determined, occurring during the 2010-2011 season has been reported.
http://www.cdc.gov/flu/weekly/

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-47

Re: FluView 2010-2011: Weeks 40-47

Week 47:
During week 47 (November 21-27, 2010), influenza activity in the United States remained relatively low overall, but increased slightly in the Southeast.

* Of the 3,430 specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division, 366 (10.7%) were positive for influenza.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
* No influenza-associated pediatric deaths were reported.
* The proportion of outpatient visits for influenza-like illness (ILI) was 1.9%, which is below the national baseline of 2.5%. One of the 10 regions (Region 4) reported ILI above region-specific baseline levels; one state (GA) experienced high ILI activity; one state experienced low ILI activity, and 48 states experienced minimal ILI activity.
* The geographic spread of influenza in one state (GA) was reported as regional, Puerto Rico and nine states reported local activity; the District of Columbia, Guam, the U.S. Virgin Islands, and 33 states reported sporadic activity; and seven states reported no influenza activity.
http://www.cdc.gov/flu/weekly/

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-48

Re: FluView 2010-2011: Weeks 40-48

Week 48:
* Of the 3,572 specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division, 386 (10.8%) were positive for influenza.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
* No influenza-associated pediatric deaths were reported.
* The proportion of outpatient visits for influenza-like illness (ILI) was 1.5%, which is below the national baseline of 2.5%. All 10 regions reported ILI below region-specific baseline levels; one state (Georgia) and New York City experienced low ILI activity and the District of Columbia and 49 states experienced minimal ILI activity.
* The geographic spread of influenza in three states (Georgia, Kentucky, and Virginia) was reported as regional, Puerto Rico and 12 states reported local activity; the District of Columbia, the U.S. Virgin Islands, and 29 states reported sporadic activity; Guam and six states reported no influenza activity.
http://www.cdc.gov/flu/weekly/

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-49

Re: FluView 2010-2011: Weeks 40-49

During week 49 (December 5-11, 2010), influenza activity in the United States increased.

* Of the 3,295 specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division, 363 (11.0%) were positive for influenza.
* One human infection with a novel influenza A virus was reported.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
* One influenza-associated pediatric death was reported and was associated with Influenza A (H3) virus infection.
* The proportion of outpatient visits for influenza-like illness (ILI) was 1.8%, which is below the national baseline of 2.5%. All 10 regions reported ILI below region-specific baseline levels; two states (Alabama and Georgia) experienced high ILI activity, New York City and three states experienced low ILI activity, 45 states experienced minimal ILI activity, and the District of Columbia had insufficient data.
* The geographic spread of influenza in Puerto Rico and four states (Georgia, Kentucky, Mississippi, and Nevada) was reported as regional, 20 states reported local activity; the District of Columbia, the U.S. Virgin Islands, and 21 states reported sporadic activity, and Guam and five states reported no influenza activity.

One case of human infection with a novel influenza A virus was reported by the Minnesota Department of Health. The patient became ill with a swine origin influenza A (H3N2) virus infection in November. Five other human illnesses from swine origin influenza A (H3N2) viruses have been previously identified in 2009 and 2010. The case reported contact with pigs in the week preceding symptom onset. The patient required hospitalization, but has since recovered.
http://www.cdc.gov/flu/weekly/

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-50

Re: FluView 2010-2011: Weeks 40-50

During week 50 (December 12-18, 2010), influenza activity in the United States increased.

* Of the 4,733 specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division, 744 (15.7%) were positive for influenza.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
* No influenza-associated pediatric deaths were reported
* The proportion of outpatient visits for influenza-like illness (ILI) was 2.1%, which is below the national baseline of 2.5%. One of the 10 regions (Region 4) reported ILI above region-specific baseline levels; three states (Alabama, Georgia, and Mississippi) experienced high ILI activity, New York City and two states experienced moderate ILI activity, two states experienced low ILI activity, and the District of Columbia and 43 states experienced minimal ILI activity.
* The geographic spread of influenza in one state (Mississippi) was reported as widespread, Puerto Rico and 13 states reported regional activity, six states reported local activity; the District of Columbia, Guam, and 29 states reported sporadic activity, one state reported no influenza activity, and the U.S. Virgin Islands did not report.
http://www.cdc.gov/flu/weekly/

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-51

Re: FluView 2010-2011: Weeks 40-51

During week 51 (December 19-25, 2010), influenza activity in the United States continued to increase.

* Of the 3,284 specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division, 689 (21.0%) were positive for influenza.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was at the epidemic threshold.
* One influenza-associated pediatric death was reported and was associated with Influenza A (H3) virus infection.
* The proportion of outpatient visits for influenza-like illness (ILI) was 2.7%, which is above the national baseline of 2.5%. Two of the 10 regions (Regions 2 and 4) reported ILI above region-specific baseline levels; three states and New York City experienced high ILI activity, six states experienced moderate ILI activity, five states experienced low ILI activity, 35 states experienced minimal ILI activity, and data were insufficient from the District of Columbia and two states.
* The geographic spread of influenza in five states was reported as widespread, Puerto Rico and 13 states reported regional activity; nine states reported local activity; the District of Columbia, the U.S. Virgin Islands, and 23 states reported sporadic activity, and Guam reported no activity.

During week 51, 7.5% of all deaths reported through the 122-Cities Mortality Reporting System were due to P&I. This percentage was at the epidemic threshold of 7.5% for week 51.

One influenza-associated pediatric death was reported to CDC during week 51 (New York City). This death was associated with an influenza A (H3) virus infection. The death reported this week occurred between December 5, 2010 and December 11, 2010.

Three influenza-associated pediatric deaths occurring during the 2010-2011 season have been reported; two deaths were associated with influenza A (H3) virus infection and one was associated with an influenza A virus for which the subtype was not determined.
http://www.cdc.gov/flu/weekly/?source=govdelivery

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-52

Re: FluView 2010-2011: Weeks 40-52

During week 52 (December 26, 2010 – January 1, 2011), influenza activity in the United States decreased slightly.

* Of the 4,911 specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division, 995 (20.3%) were positive for influenza.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
* One influenza-associated pediatric death was reported and was associated with Influenza B virus infection.
* The proportion of outpatient visits for influenza-like illness (ILI) was 2.6%, which is above the national baseline of 2.5%. Four of the 10 regions (Regions 2, 3, 4, and 5) reported ILI above region-specific baseline levels; six states and New York City experienced high ILI activity, two states experienced moderate ILI activity, six states experienced low ILI activity, 35 states experienced minimal ILI activity, and data were insufficient from the District of Columbia and one state.
* The geographic spread of influenza in eight states was reported as widespread; Puerto Rico and 16 states reported regional influenza activity; the District of Columbia and 11 states reported local influenza activity, and Guam, the U.S. Virgin Islands, and 15 states reported sporadic influenza activity.

Cumulative hospitalization rates for 2010-11 Season:
0-4 years: 6.1 per 100,000
46% of pediatric hospitalizations had no known underlying condition
http://www.cdc.gov/flu/weekly/

 

[Missouriwatcher]

Re: FluView 2010-2011: Weeks 40-1

Re: FluView 2010-2011: Weeks 40-1

During week 1 (January 2-8, 2011), influenza activity in the United States decreased in several indicators, but it is unlikely that influenza activity for this season has peaked.

* Of the 4,331 specimens tested by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories and reported to CDC/Influenza Division, 706 (16.3%) were positive for influenza.
* The proportion of deaths attributed to pneumonia and influenza (P&I) was at the epidemic threshold.
* Four influenza-associated pediatric deaths were reported. Two of these deaths were associated with influenza A (H3) viruses and two were associated with influenza B virus infection.
* The proportion of outpatient visits for influenza-like illness (ILI) was 2.2%, which is below the national baseline of 2.5%. One of the 10 regions (Region 4) reported ILI above region-specific baseline levels. Four states experienced high ILI activity, New York City experienced moderate ILI activity, four states experienced low ILI activity, 42 states experienced minimal ILI activity, and data were insufficient from the District of Columbia.
* The geographic spread of influenza in 11 states was reported as widespread; 17 states reported regional influenza activity; the District of Columbia and 16 states reported local influenza activity; the U.S. Virgin Islands, and six states reported sporadic influenza activity, and Guam reported no influenza activity.
http://www.cdc.gov/flu/weekly/