Functional immunity against SARS-CoV-2 in the general population after a booster campaign and the Delta and Omicron waves, Switzerland, March 2022

Euro Surveill. 2022 Aug;27(31):2200561. doi: 10.2807/1560-7917.ES.2022.27.31.2200561.

Abstract

Functional immunity (defined here as serum neutralising capacity) critically contributes to conferring protection against SARS-CoV-2 infection and severe COVID-19. This cross-sectional analysis of a prospective, population-based cohort study included 1,894 randomly-selected 16 to 99-year-old participants from two Swiss cantons in March 2022. Of these, 97.6% (95% CI: 96.8-98.2%) had anti-spike IgG antibodies, and neutralising capacity was respectively observed for 94%, 92% and 88% against wild-type SARS-CoV-2, Delta and Omicron variants. Studying functional immunity to inform and monitor vaccination campaigns is crucial.

Keywords: SARS-CoV-2; neutralising activity; seroprevalence; variants of concern.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Antibodies, Neutralizing
  • Antibodies, Viral
  • COVID-19 Vaccines* / administration & dosage
  • COVID-19* / immunology
  • COVID-19* / prevention & control
  • Cross-Sectional Studies
  • Humans
  • Immunization Programs
  • Immunization, Secondary
  • Middle Aged
  • Prospective Studies
  • SARS-CoV-2*
  • Spike Glycoprotein, Coronavirus / immunology
  • Switzerland / epidemiology
  • Young Adult

Substances

  • Antibodies, Neutralizing
  • Antibodies, Viral
  • COVID-19 Vaccines
  • Spike Glycoprotein, Coronavirus
  • spike protein, SARS-CoV-2

Supplementary concepts

  • SARS-CoV-2 variants