FluView : 2016-2017 influenza season week 4 ending January 28, 2017

All data are preliminary and may change as more reports are received.During week 4 (January 22-28, 2017), influenza activity increased in the United States.\u2022 Viral Surveillance: The most frequently identified influenza virus subtype reported by public health laboratories during week 4 was influenza A (H3). The percentage of respiratory specimens testing positive for influenza in clinical laboratories increased.\u2022 Pneumonia and Influenza Mortality: Due to data processing problems, the National Center for Health Statistics (NCHS) mortality surveillance data for the week ending January 14, 2015 (week 2) will not be published this week.\u2022 Influenza-associated Pediatric Deaths: Seven influenza-associated pediatric deaths were reported.\u2022 Influenza-associated Hospitalizations: A cumulative rate for the season of 20.3 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.\u2022 Outpatient Illness Surveillance:The proportion of outpatient visits for influenza-like illness (ILI) was 3.9%, which is above the national baseline of 2.2%. All 10 regions reported ILI at or above their region-specific baseline levels. New York City and 15 states experienced high ILI activity; Puerto Rico and 11 states experienced moderate ILI activity; 14 states experienced low ILI activity; 10 states experienced minimal ILI activity, and the District of Columbia had insufficient data.\u2022 Geographic Spread of Influenza: The geographic spread of influenza in Puerto Rico and 40 states was reported as widespread; Guam and nine states reported regional activity; the District of Columbia and one state reported local activity; and the U.S. Virgin Islands reported no activity.External_F1704.pdf2017713