Weekly U.S. Influenza Surveillance Report

The CDC Influenza Division collects, compiles, and analyzes information on Influenza activity year-round in the US and produces FluView, a weekly influenza surveillance report. During week 51, ending December 24, four states (Alabama, Arizona, Georgia & Oklahoma), as well as New York City, and Puerto Rico experienced high activity.

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2016-2017 Influenza Season Week 51 ending December 24, 2016

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

Synopsis:

During week 51 (December 18-24, 2016), influenza activity increased in the United States.

Viral Surveillance: The most frequently identified influenza virus subtype reported by public health laboratories during week 51 was influenza A (H3). The percentage of respiratory specimens testing positive for influenza in clinical laboratories increased.
Novel Influenza A Virus: One human infection with a novel influenza A virus was reported.
Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the system-specific epidemic threshold in the National Center for Health Statistics (NCHS) Mortality Surveillance System.
Influenza-associated Pediatric Deaths: No influenza-associated pediatric deaths were reported.
Influenza-associated Hospitalizations: A cumulative rate for the season of 3.1 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 2.9%, which is above the national baseline of 2.2%. Nine regions reported ILI at or above their region-specific baseline levels. Four states, New York City and Puerto Rico experienced high ILI activity; five states experienced moderate ILI activity; seven states experienced low ILI activity; 34 states experienced minimal ILI activity, and the District of Columbia had insufficient data.
Geographic Spread of Influenza: The geographic spread of influenza in Guam and eight states was reported as widespread, the U.S. Virgin Islands and 17 states reported regional activity, the District of Columbia and 19 states reported local activity, five states reported sporadic activity, and Puerto Rico and one state did not report.