Effectiveness of mRNA Vaccines Against COVID-19 Hospitalization by Age and Chronic Medical Conditions Burden Among Immunocompetent US Adults, March-August 2021

J Infect Dis. 2022 May 16;225(10):1694-1700. doi: 10.1093/infdis/jiab619.

Abstract

Vaccine effectiveness (VE) against COVID-19 hospitalization was evaluated among immunocompetent adults (≥18 years) during March-August 2021 using a case-control design. Among 1669 hospitalized COVID-19 cases (11% fully vaccinated) and 1950 RT-PCR-negative controls (54% fully vaccinated), VE was 96% (95% confidence interval [CI], 93%-98%) among patients with no chronic medical conditions and 83% (95% CI, 76%-88%) among patients with ≥ 3 categories of conditions. VE was similar between those aged 18-64 years versus ≥65 years (P > .05). VE against severe COVID-19 was very high among adults without chronic conditions and lessened with increasing comorbidity burden.

Keywords: COVID-19; chronic medical conditions; preexisting conditions; vaccine effectiveness.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • COVID-19 Vaccines
  • COVID-19* / epidemiology
  • COVID-19* / prevention & control
  • Chronic Disease
  • Hospitalization
  • Humans
  • Vaccines, Synthetic
  • mRNA Vaccines

Substances

  • COVID-19 Vaccines
  • Vaccines, Synthetic
  • mRNA Vaccines