# 4411
Key Influenza indicators for the latest reporting period (ending February 27th) remained about the same as in the previous week, with P&I deaths slightly elevated over week 7, but still below the epidemic threshold for this time of year.
Visits to doctors for ILI (influenza-like illnesses) are on the decline, and the vast majority (93.6%) of samples submitted to the CDC did not test positive for influenza. Other respiratory viruses, such as RSV, adenovirus, and Rhinoviruses are undoubtedly contributing to the mix.
Perhaps the most hopeful sign is that only one flu-related pediatric death was reported, and this was a delayed report from last year and did not involve the H1N1 virus.
A brief summary, therefore, of this week’s FluView highlights. Follow the link to read the entire weekly update.
2009-2010 Influenza Season Week 8 ending February 27, 2010
All data are preliminary and may change as more reports are received.
Synopsis:
During week 8 (February 21-27, 2010), influenza activity remained at approximately the same levels as last week in the U.S.
- 263 (6.4%) 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.
- Over 99% of all subtyped influenza A viruses reported to CDC were 2009 influenza A (H1N1) viruses.
- 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 B virus infection. This death occurred during the 2008-09 influenza season.
- The proportion of outpatient visits for influenza-like illness (ILI) was 1.7% which is below the national baseline of 2.3%. Two of 10 regions (Regions 4 and 9) reported ILI above region-specific baseline levels.
- No states reported widespread influenza activity, four states reported regional influenza activity, Puerto Rico and eight states reported local influenza activity, the District of Columbia, Guam, and 34 states reported sporadic influenza activity, four states reported no influenza activity, and the U.S. Virgin Islands did not report.
U.S. Virologic Surveillance:
WHO and NREVSS collaborating laboratories located in all 50 states and Washington, D.C. report to CDC the number of respiratory specimens tested for influenza and the number positive by influenza type and subtype. The results of tests performed during the current week are summarized in the table below.
Pneumonia and Influenza (P&I) Mortality Surveillance
During week 8, 7.8% of all deaths reported through the 122-Cities Mortality Reporting System were due to P&I. This percentage was below the epidemic threshold of 7.9% for week 8.
Influenza-Associated Pediatric Mortality
One influenza-associated pediatric deaths was reported to CDC during week 8 (Florida). This death was associated with an influenza B virus infection that occurred in February 2009. This brings the total number of reported pediatric deaths occurring during the 2008-09 season to 133.
Outpatient Illness Surveillance:
Nationwide during week 8, 1.7% 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 2.3%.
