Anti-SARS-CoV-2 Antibody Levels Associated with COVID-19 Protection in Outpatients Tested for SARS-CoV-2, US Flu VE Network, October 2021-June 2022

Kelsey M Sumner; Ruchi Yadav; Emma K Noble; Ryan Sandford; Devyani Joshi; Sara Y Tartof; Karen J Wernli; Emily T Martin; Manjusha Gaglani; Richard K Zimmerman; H Keipp Talbot; Carlos G Grijalva; Edward A Belongia; Jessie R Chung; Eric Rogier; Melissa M Coughlin; Brendan Flannery

doi:10.1093/infdis/jiae090

Anti-SARS-CoV-2 Antibody Levels Associated with COVID-19 Protection in Outpatients Tested for SARS-CoV-2, US Flu VE Network, October 2021-June 2022

J Infect Dis. 2024 Feb 23:jiae090. doi: 10.1093/infdis/jiae090. Online ahead of print.

Authors

Kelsey M Sumner^{1

2}, Ruchi Yadav¹, Emma K Noble^{1

3}, Ryan Sandford¹, Devyani Joshi¹, Sara Y Tartof^{4

5}, Karen J Wernli⁶, Emily T Martin⁷, Manjusha Gaglani^{8

9

10}, Richard K Zimmerman¹¹, H Keipp Talbot¹², Carlos G Grijalva¹², Edward A Belongia¹³, Jessie R Chung¹, Eric Rogier¹, Melissa M Coughlin¹, Brendan Flannery¹

Affiliations

¹ Centers for Disease Control and Prevention, Atlanta, GA, USA.
² Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, GA, USA.
³ Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, USA.
⁴ Kaiser Permanente Southern California, Department of Research & Evaluation, Pasadena, CA, USA.
⁵ Department of Health Systems Science, Kaiser Permanente Bernard J. Tyson School of Medicine, Pasadena, CA, USA.
⁶ Kaiser Permanente Washington Health Research Institute, Seattle, WA, USA.
⁷ University of Michigan School of Public Health, Ann Arbor, MI, USA.
⁸ Baylor Scott & White Health, Temple, TX, USA.
⁹ Baylor College of Medicine - Temple, Temple, TX, USA.
¹⁰ Texas A&M University College of Medicine, Temple, TX, USA.
¹¹ University of Pittsburgh, Pittsburgh, PA, USA.
¹² Vanderbilt University Medical Center, Nashville, TN, USA.
¹³ Marshfield Clinic Research Institute, Marshfield, WI, USA.

PMID: 38390968
DOI: 10.1093/infdis/jiae090

Abstract

Background: We assessed associations between binding antibody (bAb) concentration <5 days of symptom onset and testing positive for COVID-19 among patients in a test-negative study.

Methods: From October 2021─June 2022, study sites in seven states enrolled patients aged ≥6 months presenting with acute respiratory illness. Respiratory specimens were tested for SARS-CoV-2. In blood specimens, we measured concentrations of anti-SARS-CoV-2 antibodies against the ancestral strain spike protein receptor binding domain (RBD) and nucleocapsid (N) antigens in standardized binding antibody units (BAU/mL). Percent change in odds of COVID-19 by increasing anti-RBD bAb was estimated using logistic regression as (1-adjusted odds ratio of COVID-19)x100, adjusting for COVID-19 mRNA vaccine doses, age, site, and high-risk exposure.

Results: Out of 2,018 symptomatic patients, 662 (33%) tested positive for acute SARS-CoV-2 infection. Geometric mean RBD bAb were lower among COVID-19 cases than SARS-CoV-2 test-negative patients during both the Delta-predominant (112 vs. 498 BAU/mL) and Omicron-predominant (823 vs. 1,189 BAU/mL) periods. Acute phase ancestral spike RBD bAb associated with 50% lower odds of COVID-19 were 1,968 BAU/mL against Delta and 3,375 BAU/mL against Omicron; thresholds may differ in other laboratories.

Conclusion: During acute illness, antibody concentrations against ancestral spike RBD were associated with protection against COVID-19.

Keywords: COVID-19; SARS-CoV-2 infection; antibodies; correlates of protection.