Weekly U.S. Influenza Surveillance Report | Seasonal Influenza (Flu) | CDC

Weekly U.S. Influenza Surveillance Report | Seasonal Influenza (Flu) | CDC

2014-2015 Influenza Season Week 20 ending May 23, 2015

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

Synopsis:

During week 20 (May 17-23, 2015), influenza activity continued to decrease in the United States.

• Viral Surveillance: Of 6,337 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 20, 185 (2.9%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
• Influenza-associated Pediatric Deaths: Two influenza-associated pediatric deaths were reported.
• Influenza-associated Hospitalizations: A cumulative rate for the season of 65.5 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 1.2%, which is below the national baseline of 2.0%. All 10 regions reported ILI below region-specific baseline levels. One state experienced low ILI activity; Puerto Rico, New York City, and 49 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 one state was reported as regional; Puerto Rico and six states reported local activity; the District of Columbia and 32 states reported sporadic activity; and the U.S. Virgin Islands and 11 states reported no influenza activity.