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[Preprint]. 2023 Sep 23:2023.09.21.23295919.
doi: 10.1101/2023.09.21.23295919.

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  1   2 , Ruchi Yadav  1 , Emma K Noble  1   3 , Ryan Sandford  1 , Devyani Joshi  1 , Sara Y Tartof  4   5 , Karen J Wernli  6 , Emily T Martin  7 , Manjusha Gaglani  8   9 , Richard K Zimmerman  10 , H Keipp Talbot  11 , Carlos G Grijalva  11 , Jessie R Chung  1 , Eric Rogier  1 , Melissa M Coughlin  1 , Brendan Flannery  1
Affiliations

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 et al. medRxiv. .

Abstract

Background: We assessed the association between antibody concentration ≤5 days of symptom onset and COVID-19 illness among patients enrolled in a test-negative study.

Methods: From October 2021-June 2022, study sites in seven states enrolled and tested respiratory specimens from patients of all ages presenting with acute respiratory illness for SARS-CoV-2 infection using rRT-PCR. In blood specimens, we measured concentration 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 reduction in odds of symptomatic COVID-19 by anti-RBD antibody was estimated using logistic regression modeled as (1-adjusted odds ratio of COVID-19)×100, adjusting for COVID-19 vaccination status, age, site, and high-risk exposure.

Results: A total of 662 (33%) of 2,018 symptomatic patients tested positive for acute SARS-CoV-2 infection. During the Omicron-predominant period, geometric mean anti-RBD binding antibody concentrations measured 823 BAU/mL (95%CI:690-981) among COVID-19 case-patients versus 1,189 BAU/mL (95%CI:1,050-1,347) among SARS-CoV-2 test-negative patients. In the adjusted logistic regression, increasing levels of anti-RBD antibodies were associated with reduced odds of COVID-19 for both Delta and Omicron infections.

Conclusion: Higher anti-RBD antibodies in patients were associated with protection against symptomatic COVID-19 during emergence of SARS-CoV-2 Delta and Omicron variants.

Keywords: SARS-CoV-2; correlates of protection; immunogenicity.

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Conflict of interest statement

CONFLICTS OF INTEREST Dr. Zimmerman reports grants from CDC, during the conduct of the study, and grants from Sanofi Pasteur, outside the submitted work. Dr. Grijalva reports other from CDC, grants from NIH, other from FDA, grants and other from AHRQ, other from Merck, and other from Syneos Health, outside the submitted work. Dr. Talbot reports grants from CDC, during the conduct of the study. All other authors report not conflicts of interest.

Figures

Figure 1.
Figure 1.. US Influenza Vaccine Effectiveness Network enrollment for 2021–22 season.
The number of patients enrolled in the US Flu VE Network and included in the final analytic data set are shown, detailing each of the exclusion criterion applied. The Delta-predominant period was from October 1–December 24, 2021, and the Omicron-predominant period from December 25, 2021–June 29, 2022.
Figure 2.
Figure 2.. Association between SARS-CoV-2 anti-spike receptor binding domain (RBD) IgG antibodies and likelihood of symptomatic COVID-19.
2A. Bars indicate the number of COVID-19 case (darker shading) and test-negative control (lighter shading) patients within each anti-RBD binding antibody unit (BAU) category. The line represents SARS-CoV-2 rRT-PCR test positivity within each anti-RBD binding antibody category. Results presented stratified by the Delta (orange) and Omicron (grey) variant periods. The Delta-predominant period was from October 1–December 24, 2021, and the Omicron-predominant period from December 25, 2021–June 29, 2022. 2B. The percent odds reduction in COVID-19 illness by anti-RBD binding antibody level is presented stratified by the Delta (orange) and Omicron (grey) variant periods. Percent odds reduction was estimated as (1-adjusted odds ratio) × 100, using the adjusted odds ratio produced by a logistic regression model adjusted for COVID-19 vaccination status, age, study site, illness onset week, and high-risk SARS-CoV-2 exposure.
See this image and copyright information in PMC

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