title: Estimates of mortality attributable to influenza and RSV in the United States during 1997-2009 by influenza type or subtype, age, cause of death, and risk status.
abstract: BACKGROUND
  Influenza and respiratory syncytial virus (RSV) cause substantial mortality from respiratory and other causes in the USA, especially among people aged 65 and older.
  
  
  OBJECTIVE
  We estimated the influenza-attributable mortality and RSV-attributable mortality in the USA, stratified by age and risk status, using outcome definitions with different sensitivity and specificity.
  
  
  METHODS
  Influenza- and RSV-associated mortality was assessed from October 1997-March 2009 using multiple linear regression modeling on data obtained from designated government repositories.
  
  
  RESULTS
  The main outcomes and measures included mortality outcome definitions-pneumonia and influenza, respiratory broad, and cardiorespiratory disease. A seasonal average of 10,682 (2287-16,363), 19,100 (4862-29,245), and 28,169 (6797-42,316) deaths was attributed to influenza for pneumonia and influenza, respiratory broad, and cardiorespiratory outcome definitions, respectively. Corresponding values for RSV were 6211 (4584-8169), 11,300 (8546-14,244), and 17,199 (13,384-21,891), respectively. A/H3N2 accounted for seasonal average of 71% influenza-attributable deaths; influenza B accounted for most (51-95%) deaths during four seasons. Approximately 70% influenza-attributable deaths occurred in individuals ≥75 years, with increasing mortality for influenza A/H3N2 and B, but not A/H1N1. In children aged 0-4 years, an average of 97 deaths was attributed to influenza (A/H3N2 = 49, B = 33, A/H1N1 = 15) and 165 to respiratory broad outcome definition (RSV). Influenza-attributable mortality was 2.94-fold higher in high-risk individuals.
  
  
  CONCLUSIONS
  Influenza-attributable mortality was highest in older and high-risk individuals and mortality in children was higher than reported in passive Centers for Disease Control and Prevention surveillance. Influenza B-attributable mortality was higher than A in four of 12 seasons. Our estimates represent an updated assessment of influenza-attributable mortality in the USA.
authors: GlaxoSmithKline Vaccines, Wavre, Belgium.
authors: Gonçalo
authors: G
authors: Matias
authors: Robert
authors: R
authors: Taylor
authors: François
authors: F
authors: Haguinet
authors: Cynthia
authors: C
authors: Schuck-Paim
authors: Roger
authors: R
authors: Lustig
authors: Vivek
authors: V
authors: Shinde
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007251:Influenza, Human / Q000453:epidemiology / Q000401:mortality* / Q000821:virology; D008297:Male; D008875:Middle Aged; D009975:Orthomyxoviridae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D018357:Respiratory Syncytial Virus Infections / Q000453:epidemiology / Q000401:mortality* / Q000821:virology; D012136:Respiratory Syncytial Viruses / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D012621:Seasons; D014481:United States / Q000453:epidemiology; D055815:Young Adult
keywords: A/H3N2; A/HINI; influenza; mortality; respiratory broad; respiratory syncytial virus