Update: influenza activity--United States, September 28, 2008-April 4, 2009, and composition of the 2009-10 influenza vaccine.
This report summarizes U.S. influenza activity from September 28, 2008, the start of the 2008-09 influenza season, through April 4, 2009, and reports on the 2009-10 influenza vaccine strain selection. Low levels of influenza activity were reported from October through early January. Activity increased from mid-January and peaked in mid-February. Influenza A (H1N1) viruses have predominated overall this season, but influenza B viruses have been isolated more frequently than influenza A viruses since mid-March. Widespread oseltamivir resistance was detected among circulating influenza A (H1N1) viruses and a high level of adamantane resistance was identified among influenza A (H3N2) viruses.
D000293:Adolescent; D000328:Adult; D000956:Antigens, Viral; D002648:Child; D002675:Child, Preschool; D024882:Drug Resistance, Viral; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D053118:Influenza A Virus, H1N1 Subtype / Q000187:drug effects / Q000302:isolation & purification; D053122:Influenza A Virus, H3N2 Subtype / Q000187:drug effects / Q000302:isolation & purification; D009980:Influenza A virus / Q000302:isolation & purification; D009981:Influenza B virus / Q000187:drug effects / Q000302:isolation & purification; D007252:Influenza Vaccines; D007251:Influenza, Human / Q000188:drug therapy / Q000453:epidemiology*; D011014:Pneumonia / Q000401:mortality; D011159:Population Surveillance; D014481:United States / Q000453:epidemiology; D055815:Young Adult
D000956:Antigens, Viral; D007252:Influenza Vaccines