Seroprevalence of SARS-CoV-2 antibodies in front-line pediatric health care workers

Objective The goal of this study was to determine the prevalence of SARS-CoV-2 infections in pediatric front-line health care workers (HCWs) using SARS-CoV-2 serum antibodies as an indicator of infection. Methods In this cross-sectional study, we collected blood samples and survey responses from HCWs in a 38-bed pediatric emergency department. Serum antibodies to SARS-CoV-2 (IgM and/or IgG) were measured using a 2-step enzyme-linked immunosorbent assay (ELISA) to detect antibodies against the Spike protein receptor binding domain (RBD), the ectodomain of Spike (S), and the nucleoprotein (N). Results We collected survey responses and serum samples from 54 pediatric front-line HCWs from October 2020 through April 2021. Among the 29 unvaccinated HCWs, 4 (13.7%) had antibodies to SARS-CoV-2. For the 25 vaccinated HCWs, 10 (40%) were seropositive; 3 were <10 days from the first vaccine dose and 7 were >= 10 days after the first dose. Two of the 10 seropositive vaccines had a prior positive reverse transcription polymerase chain reaction test. Individuals >= 10 days from receiving the first vaccine dose were 37.5 (95% CI: 3.5-399.3) times more likely to have SARS-CoV-2 antibodies than unvaccinated individuals or those <10 days from first vaccine dose. Conclusions Evidence of widespread SARS-CoV-2 infections was not found in unvaccinated front-line HCWs from a pediatric ED as of April 2021. Future work will be required to determine the reasons underlying the lower SARS-CoV-2 antibody prevalence compared to adult HCWs.