2016-2017 Influenza Season Week 16 ending April 22, 2017
May 1st, 2017Synopsis:
During week 16 (April 16-22, 2017), influenza activity decreased in the United States.
- Viral Surveillance: The most frequently identified influenza virus type reported by public health laboratories during week 16 was influenza B. The percentage of respiratory specimens testing positive for influenza in clinical laboratories decreased.
- 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:Six influenza-associated pediatric deaths were reported.
- Influenza-associated Hospitalizations:A cumulative rate for the season of 62.7 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 1.8%, which is below the national baseline of 2.2%. Two of ten regions reported ILI at or above their region-specific baseline levels. Four states experienced low ILI activity; New York City, Puerto Rico, and 46 states experienced minimal ILI activity; and the District of Columbia had insufficient data.
- Geographic Spread of Influenza: The geographic spread of influenza in seven states was reported as widespread; Guam, Puerto Rico and 11 states reported regional activity; the District of Columbia and 19 states reported local activity; 13 states reported sporadic activity; and the U.S. Virgin Islands reported no activity.
