Prevalence of SARS-CoV-2 Antibodies in New York City Adults, June–October 2020: A Population-Based Survey

Abstract Background Serosurveys help to ascertain burden of infection. Prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serosurveys in New York City (NYC) used nonrandom samples. During June–October 2020, the NYC Health Department conducted a population-based survey estimating SARS-CoV-2 antibody prevalence in NYC adults. Methods Participants were recruited from the NYC 2020 Community Health Survey. We estimated citywide and stratified antibody prevalence using a hybrid design: serum tested with the DiaSorin LIAISON SARS-CoV-2 S1/S2 IgG assay and self-reported antibody test results were used together. We estimated univariate frequencies and 95% confidence intervals (CI), accounting for complex survey design. Two-sided P values ≤ .05 were statistically significant. Results There were 1074 respondents; 497 provided blood and 577 provided only a self-reported antibody test result. Weighted prevalence was 24.3% overall (95% CI, 20.7%–28.3%). Latino (30.7%; 95% CI, 24.1%–38.2%; P