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

Synopsis: During week 41 (October 7-13, 2012), influenza activity remained low in the United States.

o Viral Surveillance: Of 3,285 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 41, 129 (3.9%) were positive for influenza.

o Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was at the epidemic threshold.

o Influenza-associated Pediatric Deaths: One influenza-associated pediatric death was reported and was associated with an influenza A virus for which the subtype was not determined.

o Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 1.1%, which is below the national baseline of 2.2%. All 10 regions reported ILI below region-specific baseline levels. Forty-eight states and New York City experienced minimal ILI activity and the District of Columbia and two states had insufficient data.

o Geographic Spread of Influenza: The geographic spread of influenza in one state (Iowa) was reported as local; the District of Columbia and 32 states reported sporadic activity; Guam and 16 states reported no influenza activity, and Puerto Rico, the U.S. Virgin Islands, and one state did not report.

Stephen B. Thacker CDC Library collection

United States