College Textbook Blog

2009-2010 Influenza Season Week 42 ending October 24, 2009

from the www.cdc.gov

All data are preliminary and may change as more reports are received.

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.