title: Update: Influenza activity - United States, September 30, 2012-February 9, 2013.
abstract: Influenza activity in the United States began to increase in mid-November and remained elevated through February 9, 2013. During that time, influenza A (H3N2) viruses predominated overall, followed by influenza B viruses. This report summarizes U.S. influenza activity* since the beginning of the 2012-13 influenza season and updates the previous summary.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D024882:Drug Resistance, Viral; D005260:Female; 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*; D009981:Influenza B virus / Q000187:drug effects / Q000302:isolation & purification*; D007252:Influenza Vaccines / Q000008:administration & dosage; D007251:Influenza, Human / Q000401:mortality* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D010045:Outpatients; D011159:Population Surveillance; D014481:United States / Q000453:epidemiology; D014611:Vaccination; D055815:Young Adult
chemical_list: D007252:Influenza Vaccines