Transition to endemicity: Understanding COVID-19

Immunity. 2021 Oct 12;54(10):2172-2176. doi: 10.1016/j.immuni.2021.09.019. Epub 2021 Sep 24.


The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated disease, coronavirus disease 2019 (COVID-19), has caused a devastating pandemic worldwide. Here, we explain basic concepts underlying the transition from an epidemic to an endemic state, where a pathogen is stably maintained in a population. We discuss how the number of infections and the severity of disease change in the transition from the epidemic to the endemic phase and consider the implications of this transition in the context of COVID-19.

Publication types

  • Review

MeSH terms

  • COVID-19 / epidemiology*
  • COVID-19 / immunology*
  • COVID-19 / prevention & control
  • Disease Susceptibility / epidemiology
  • Disease Susceptibility / immunology
  • Endemic Diseases*
  • Epidemics
  • Humans
  • Immunity
  • Prevalence
  • SARS-CoV-2 / immunology
  • Severity of Illness Index
  • Vaccination