BackgroundStudies reporting estimates of the seroprevalence SERO
of severe acute respiratory syndrome coronavirus 2 MESHD
( SARS-CoV-2) antibodies SERO
have rapidly emerged. We aimed to synthesize seroprevalence SERO
data to better estimate the burden of SARS-CoV-2 infection MESHD
, identify high-risk groups, and inform public health decision making.
MethodsIn this systematic review and meta-analysis, we searched publication databases, preprint servers, and grey literature sources for seroepidemiological study reports, from January 1, 2020 to August 28, 2020. We included studies that reported a sample size, study date, location, and seroprevalence SERO
estimate. Estimates were corrected for imperfect test accuracy with Bayesian measurement error models. We conducted meta-analysis to identify demographic differences in the prevalence SERO
of SARS-CoV-2 antibodies SERO
, and meta-regression to identify study-level factors associated with seroprevalence SERO
. We compared region-specific seroprevalence SERO
data to confirmed cumulative incidence. PROSPERO: CRD42020183634.
FindingsWe identified 338 seroprevalence SERO
studies including 2.3 million participants in 50 countries. Seroprevalence SERO
was low in the general population (median 3.2%, IQR 1.0-6.4%) and slightly higher in at-risk populations (median 5.4%, IQR 1.5-18.4%). Median seroprevalence SERO
varied by WHO Global Burden of Disease region (p < 0.01), from 1.0% in Southeast Asia, East Asia and Oceania to 18.8% in South Asia. National studies had lower seroprevalence SERO
estimates than local (p = 0.02) studies. Compared to White persons, Black persons ( prevalence SERO
ratio [RR] 2.34, 95% CI 1.60-3.43) and Asian persons (RR 1.56, 95% CI 1.22-2.01) were more likely to be seropositive. Seroprevalence SERO
was higher among people ages TRANS
18-64 compared to 65 and over (RR 1.26, 95% CI 1.04-1.52). Health care workers had a 1.74x (95% CI: 1.18-2.58) higher risk compared to the general population. There was no difference in seroprevalence SERO
between sexes. There were 123 studies (36%) at low or moderate risk of bias. Seroprevalence SERO
estimates from national studies were median 11.9 (IQR 8.0 - 16.6) times higher than the corresponding SARS-CoV-2 cumulative incidence.
InterpretationMost of the population remains susceptible to SARS-CoV-2 infection MESHD
. Public health measures must be improved to protect disproportionately affected groups, including non-White people and adults TRANS
. Measures taken in SE Asia, E Asia and Oceania, and Latin America and Caribbean may have been more effective in controlling virus transmission TRANS
than measures taken in other regions.
FundingPublic Health Agency of Canada through the COVID-19 MESHD
Immunity Task Force.