Age-Specific Incidence of Influenza A Responds to Change in Virus Subtype Dominance

Clin Infect Dis. 2020 Oct 23;71(7):e195-e198. doi: 10.1093/cid/ciaa075.


When H3N2 replaced H1N1 as the dominant influenza A subtype during the 2018-2019 season, the pattern of age-specific incidence shifted due to the lingering effects of antigenic imprinting. The characteristic shape that imprinting leaves on influenza susceptibility could foster important advances in understanding and predicting the epidemiology of influenza.

Keywords: age-specific analysis; antigenic imprinting; cohort effect; influenza incidence.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Hemagglutinin Glycoproteins, Influenza Virus
  • Humans
  • Incidence
  • Influenza A Virus, H1N1 Subtype*
  • Influenza A Virus, H3N2 Subtype
  • Influenza, Human* / epidemiology
  • Seasons


  • Hemagglutinin Glycoproteins, Influenza Virus

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