Immune and behavioral correlates of protection against symptomatic post-vaccination SARS-CoV-2 infection

Front Immunol. 2024 Mar 19:15:1287504. doi: 10.3389/fimmu.2024.1287504. eCollection 2024.

Abstract

Introduction: We sought to determine pre-infection correlates of protection against SARS-CoV-2 post-vaccine inzfections (PVI) acquired during the first Omicron wave in the United States.

Methods: Serum and saliva samples from 176 vaccinated adults were collected from October to December of 2021, immediately before the Omicron wave, and assessed for SARS-CoV-2 Spike-specific IgG and IgA binding antibodies (bAb). Sera were also assessed for bAb using commercial assays, and for neutralization activity against several SARS-CoV-2 variants. PVI duration and severity, as well as risk and precautionary behaviors, were assessed by questionnaires.

Results: Serum anti-Spike IgG levels assessed by research assay, neutralization titers against Omicron subvariants, and low home risk scores correlated with protection against PVIs after multivariable regression analysis. Commercial assays did not perform as well as research assay, likely due to their lower dynamic range.

Discussion: In the 32 participants that developed PVI, anti-Spike IgG bAbs correlated with lower disease severity and shorter duration of illness.

Keywords: COVID-19; SARS-CoV-2; correlates of immunity; respiratory infection; vaccination.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antibodies, Viral
  • COVID-19 Vaccines
  • COVID-19* / prevention & control
  • Humans
  • Immunoglobulin G
  • SARS-CoV-2

Substances

  • COVID-19 Vaccines
  • Antibodies, Viral
  • Immunoglobulin G

Supplementary concepts

  • SARS-CoV-2 variants

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. The protocol was executed by the Infectious Disease Clinical Research Program (IDCRP), a Department of Defense (DoD) program executed by the Uniformed Services University of the Health Sciences (USUHS) through a cooperative agreement by the Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF). This work was supported in whole, or in part, with federal funds from the Defense Health Program (HU00012020067, HU00012120094) and the Immunization Healthcare Branch (HU00012120104) of the Defense Health Agency, United States Department of Defense, and the National Institute of Allergy and Infectious Disease (HU00011920111), under Inter-Agency Agreement Y1-AI-5072, by the Armed Forces Health Surveillance Division (AFHSD), Global Emerging Infections Surveillance (GEIS) Branch, under award ProMIS ID P0099_22_NM and Navy WUN A1417, and by the US Food and Drug Administration Medical Countermeasures Initiative grant # OCET, 2022-1750. The sponsors had no involvement in the study design, the collection of data, the analysis of data, the interpretation of data, the writing of the report, or in the decision to submit the article for publication.