Synopsis: During week 42 (Oc to ber 13-19, 2013), influenza activity remained low in the United States.

o Viral Surveillance: Of 3,513 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 42, 135 (3.8%) were positive for influenza.

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

o Influenza-associated Pediatric Deaths :Twoinfluenza-associated pediatric deaths that occurred during the 2012-2013 season were reported.

o Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 1.2%, below the national baseline of 2.0%. All 10 regions reported ILI below region-specific baseline levels. Two states experienced low ILI activity, 48 states and New York City experienced minimal ILI activity and the District of Columbia had insufficient data.

o Geographic Spread of Influenza: The geographic spread of influenza in Puerto Rico was reported as regional; 3 states reported local influenza activity; Guam, the District of Columbia, and 28 states reported sporadic influenza activity, and the U.S. Virgin Islands and 19 states reported no influenza activity.

Stephen B. Thacker CDC Library collection

United States