Synopsis: During week 10 (March 8-14, 2015), influenza activity continued to decrease, but remained elevated in the United States.

o ViralSurveillance:Of15,033specimenstestedandreportedbyU.S.WorldHealth Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 10, 1,685 (11.2%) were positive for influenza.

o PneumoniaandInfluenzaMortality:Theproportionofdeathsattributedtopneumoniaand influenza (P&I) was above the epidemic threshold.

o Influenza-associatedPediatricDeaths:Threeinfluenza-associatedpediatricdeathswere reported.

o Influenza-associatedHospitalizations:Acumulativeratefortheseasonof57.1 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.

o OutpatientIllnessSurveillance:Theproportionofoutpatientvisitsforinfluenza-likeillness (ILI) was 2.3%, above the national baseline of 2.0%. Eight regions reported ILI at or above region-specific baseline levels. Puerto Rico and four states experienced high ILI activity; six states experienced moderate ILI activity; six states experienced low ILI activity; New York City and 34 states experienced minimal ILI activity; and the District of Columbia had insufficient data.

o GeographicSpreadofInfluenza:Thegeographicspreadofinfluenzainsevenstateswas reported as widespread; Guam and 29 states reported regional activity; Puerto Rico and 13 states reported local activity; the District of Columbia and one state reported sporadic activity; and the U.S. Virgin Islands did not report.

Stephen B. Thacker CDC Library collection

United States