CDC Flu Map: Week Ending 12/22/12

Synopsis:

During week 51 (December 16-22), influenza activity increased in the U.S.

• Viral Surveillance: Of 6,234 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories in week 51, 1,846 (29.6%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
• Influenza-Associated Pediatric Deaths: Eight influenza-associated pediatric deaths were reported. Three were associated with influenza B viruses, 3 were associated with influenza A (H3) viruses, and 2 were associated with influenza A viruses for which the subtype was not determined.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 4.2%; above the national baseline of 2.2%. Nine of 10 regions reported ILI above region-specific baseline levels. New York City and 16 states experienced high ILI activity; 8 states experienced moderate ILI activity; 10 states experienced low ILI activity; 14 states experienced minimal ILI activity, and the District of Columbia and 2 states had insufficient data.
• Geographic Spread of Influenza: Thirty-one states reported widespread geographic influenza activity; 14 states reported regional activity; the District of Columbia and 3 states reported local activity; 2 states reported sporadic activity; Guam reported no influenza activity, and Puerto Rico and the U.S. Virgin Islands did not report.