Determinants and Dynamics of SARS-CoV-2 Infection in a Diverse Population: 6-Month Evaluation of a Prospective Cohort Study

Daniel B. Horton, Emily S. Barrett, Jason Roy, Maria Laura Gennaro, Tracy Andrews, Patricia Greenberg, Natalie Bruiners, Pratik Datta, Rahul Ukey, Senthil K. Velusamy, Daniel Fine, William J. Honnen, Yue Sandra Yin, Abraham Pinter, Andrew Brooks, Jay Tischfield, Sabiha Hussain, Sugeet Jagpal, Shobha Swaminathan, Veenat Parmar, Nancy Reilly, Sunanda Gaur, Reynold A. Panettieri, Jeffrey Carson, Martin J. Blaser

Publication Date: 10/15/2021

Background: We studied risk factors, antibodies, and symptoms of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in a diverse, ambulatory population. Methods: A prospective cohort (n = 831) previously undiagnosed with SARS-CoV-2 infection underwent serial testing (SARS-CoV-2 polymerase chain reaction, immunoglobulin G [IgG]) for 6 months. Results: Ninety-three participants (11.2%) tested SARS-CoV-2-positive: 14 (15.1%) asymptomatic, 24 (25.8%) severely symptomatic. Healthcare workers (n = 548) were more likely to become infected (14.2% vs 5.3%; adjusted odds ratio, 2.1; 95% confidence interval, 1.4-3.3) and severely symptomatic (29.5% vs 6.7%). IgG antibodies were detected after 79% of asymptomatic infections, 89% with mild-moderate symptoms, and 96% with severe symptoms. IgG trajectories after asymptomatic infections (slow increases) differed from symptomatic infections (early peaks within 2 months). Most participants (92%) had persistent IgG responses (median 171 days). In multivariable models, IgG titers were positively associated with symptom severity, certain comorbidities, and hospital work. Dyspnea and neurologic changes (including altered smell/taste) lasted ≥ 120 days in ≥ 10% of affected participants. Prolonged symptoms (frequently more severe) corresponded to higher antibody levels. Conclusions: In a prospective, ethnically diverse cohort, symptom severity correlated with the magnitude and trajectory of IgG production. Symptoms frequently persisted for many months after infection. Clinical Trials Registration. NCT04336215.