Effectiveness of Bivalent Omicron-Containing Booster Vaccines against SARS-CoV-2 Omicron Variant among Individuals with and without Prior SARS-CoV-2 Infection

Viruses. 2023 Aug 17;15(8):1756. doi: 10.3390/v15081756.

Abstract

In this study, we evaluated the effectiveness of the bivalent mRNA COVID-19 vaccines against the Omicron variant in individuals with or without prior SARS-CoV-2 infection history. We assessed the SARS-CoV-2-specific neutralizing antibody in serum samples by surrogate virus neutralizing assay (sVNT) and determined the serum's neutralizing capacity against the Omicron BA.5 by a plaque reduction neutralizing test (PRNT50). The results of the sVNT assay demonstrate a higher percentage of inhibition of the serum samples from the infected group than from the uninfected group (p = 0.01) before the bivalent vaccination but a similarly high percentage of inhibition after the vaccination. Furthermore, the results of the PRNT50 assay demonstrate a higher neutralizing capacity of the serum samples against Omicron BA.5 in the infected group compared to the uninfected group, both before and after the bivalent vaccine administration (p < 0.01 and p = 0.02 for samples collected before and after the bivalent vaccination, respectively). A higher neutralizing capacity of the serum samples against BA.5 following bivalent vaccination compared to those before vaccination suggests the efficacy of bivalent mRNA COVID-19 vaccines in triggering an immune response against the Omicron variant, particularly BA.5, regardless of infection history.

Keywords: COVID-19; Omicron variant; SARS-CoV-2; bivalent mRNA vaccine; neutralizing antibody.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Viral
  • COVID-19 Vaccines
  • COVID-19* / prevention & control
  • Humans
  • RNA, Messenger
  • SARS-CoV-2 / genetics

Substances

  • COVID-19 Vaccines
  • Antibodies, Viral
  • RNA, Messenger

Supplementary concepts

  • SARS-CoV-2 variants

Grants and funding

This research was supported by the National Research Foundation (NRF) of Korea (NRF-2021R1I1A3044483, NRF-2021M3E5E3080382, and NRF-2021M3E5E3080379) and KRIBB Research Initiative Program (KGM5472322). The funders had no role in the study design, data collection, interpretation, or decision to submit the manuscript for publication.