Cumulative Incidence of SARS-CoV-2 Infections Among Adults in Georgia, United States, August to December 2020

• Type of Material: Article
• Authors: Allison Chamberlain, Emory University; Kathleen E Toomey, Georgia Department of Public Health; Heather Bradley, Georgia State University; Eric W Hall, Emory University; Mansour Fahimi, Marketing Systems Group; Benjamin Lopman, Emory University; Nicole Luisi, Emory University; Travis Sanchez, Emory University; Cherie Drenzek, Georgia Department of Public Health; Kayoko Shioda, Emory University; Aaron Siegler, Emory University; Patrick Sullivan, Emory University
• Language: English
• Date: 2022-02-01
• Publisher: OXFORD UNIV PRESS INC
• Publication Version: Final Published Version
• Copyright Statement: © The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1093/infdis/jiab522
• Title of Journal or Parent Work: JOURNAL OF INFECTIOUS DISEASES
• Volume: 225
• Issue: 3
• Start Page: 396
• End Page: 403
• Grant/Funding Information: This work was supported by the National Institute of Allergy and Infectious Diseases (grant number 3R01AI143875-02S1); the Center for AIDS Research at Emory University (grant number P30AI050409); a grant from the California Department of Health; and the Robert W. Woodruff Foundation through a grant to the Emory Covid-19 Response Collaborative.
• Keywords: Microbiology; ANTIBODIES; seroprevalence; Science & Technology; PREVALENCE; Georgia; SARS-CoV-2; cumulative incidence; COVID-19; Infectious Diseases; Immunology; Life Sciences & Biomedicine
• Research Categories: Health Sciences, Public Health; Health Sciences, Epidemiology

Abstract

Background: Reported coronavirus disease 2019 (COVID-19) cases underestimate true severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Data on all infections, including asymptomatic infections, are needed. To minimize biases in estimates from reported cases and seroprevalence surveys, we conducted a household-based probability survey and estimated cumulative incidence of SARS-CoV-2 infections adjusted for antibody waning. Methods: From August to December 2020, we mailed specimen collection kits (nasal swabs and blood spots) to a random sample of Georgia addresses. One household adult completed a survey and returned specimens for virus and antibody testing. We estimated cumulative incidence of SARS-CoV-2 infections adjusted for waning antibodies, reported fraction, and infection fatality ratio (IFR). Differences in seropositivity among demographic, geographic, and clinical subgroups were explored with weighted prevalence ratios (PR). Results: Among 1370 participants, adjusted cumulative incidence of SARS-CoV-2 was 16.1% (95% credible interval [CrI], 13.5%-19.2%) as of 16 November 2020. The reported fraction was 26.6% and IFR was 0.78%. Non-Hispanic black (PR, 2.03; 95% confidence interval [CI], 1.0-4.1) and Hispanic adults (PR, 1.98; 95% CI,. 74-5.31) were more likely than non-Hispanic white adults to be seropositive. Conclusions: As of mid-November 2020, 1 in 6 adults in Georgia had been infected with SARS-CoV-2. The COVID-19 epidemic in Georgia is likely substantially underestimated by reported cases.