Health care workers (HCWs) are at higher risk for SARS-CoV-2 infection and may play a role in transmitting the infection to vulnerable patients and members of the community. This is particularly worrisome in the context of asymptomatic infection. We performed a cross-sectional study looking at asymptomatic SARS-CoV-2 infection in HCWs. We screened asymptomatic HCWs for SARS-CoV-2 via PCR. Complementary viral genome sequencing was performed on positive swab specimens. A seroprevalence analysis was also performed using multiple assays. Asymptomatic health care worker cohorts had a combined swab positivity rate of 29/5776 (0.50%, 95%CI 0.32–0.75) relative to a comparative cohort of symptomatic HCWs, where 54/1597 (3.4%) tested positive for SARS-CoV-2 (ratio of symptomatic to asymptomatic 6.8:1). SARS-CoV-2 seroprevalence among 996 asymptomatic HCWs with no prior known exposure to SARS-CoV-2 was 1.4–3.4%, depending on assay. A novel in-house Coronavirus protein microarray showed differing SARS-CoV-2 protein reactivities and helped define likely true positives vs. suspected false positives. Our study demonstrates the utility of routine screening of asymptomatic HCWs, which may help to identify a significant proportion of infections.
【초록키워드】 SARS-CoV-2, coronavirus, Health care, cross-sectional, SARS-COV-2 infection, health care workers, Infection, Protein, Cohort, Health, infections, cross-sectional study, Viral, PCR, SARS-CoV-2 seroprevalence, Asymptomatic, HCWs, symptomatic, asymptomatic infection, Microarray, Community, Swab, utility, Care, specimens, Analysis, False positives, HCW, exposure to, 95%CI, higher risk, house, help, Viral genome sequencing, SARS-CoV-2 protein, true positives, positive, positive swab, vulnerable patients, tested, identify, performed, proportion, assays, was performed, screened, reactivity, true positive, vulnerable patient, 【제목키워드】 healthcare worker, Serosurvey, Prospective, Care,