Friday, October 30, 2009

FluView Week 42

 

# 3916

 

 

The CDC has posted FluView for week 42, ending October 24th, 2009. The level of activity we are seeing is roughly what we might expect during the height of the flu season, not during  mid-to-late October.

 

I’ve excerpted some of the data and graphs below, but follow the link to read it in its entirety.

 

Synopsis:

During week 42 (October 18-24, 2009), influenza activity increased in the U.S.

  • 8,268 (42.1%) 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.
  • All subtyped influenza A viruses being reported to CDC were 2009 influenza A (H1N1) viruses.
  • The proportion of deaths attributed to pneumonia and influenza (P&I) was above the epidemic threshold.
  • Twenty-two influenza-associated pediatric deaths were reported. Nineteen of these deaths were associated with 2009 influenza A (H1N1) virus infection and three were associated with an influenza A virus for which the subtype was undetermined.
  • The proportion of outpatient visits for influenza-like illness (ILI) was above the national baseline. All 10 regions reported ILI above region-specific baseline levels.
  • Forty-eight states reported geographically widespread influenza activity, Guam and two states reported regional influenza activity, the District of Columbia and Puerto Rico reported local 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.

image

 

 

Pneumonia and Influenza (P&I) Mortality Surveillance

During week 42, 7.1% of all deaths reported through the 122-Cities Mortality Reporting System were due to P&I. This percentage was above the epidemic threshold of 6.6% for week 42. Including week 42, P&I mortality has been above threshold for four consecutive weeks.

image

 

 

Influenza-Associated Pediatric Mortality

Twenty-two influenza-associated pediatric deaths were reported to CDC during week 42 (Arizona [3], Florida, Georgia, Guam, Montana, Ohio, South Dakota, Tennessee [2], Texas [9], Washington, and Wisconsin). Nineteen of these deaths were associated with 2009 influenza A (H1N1) virus infection and three were associated with an influenza A virus for which the subtype is undetermined.

 

These deaths occurred between August 23 and October 24, 2009. One death reported during week 42 occurred during the 2008-09 season. Since August 30, 2009, CDC has received 74 reports of influenza-associated pediatric deaths that occurred during the current influenza season (nine deaths in children less than 2 years old, nine deaths in children 2-4 years old, 27 deaths in children 5-11 years old, and 29 deaths in individuals 12-17 years old).

 

Sixty-five of the 74 deaths were due to 2009 influenza A (H1N1) virus infections, and the remaining nine were associated with influenza A virus for which the subtype is undetermined. A total of 114 deaths in children associated with 2009 H1N1 virus have been reported to CDC.

image