key: cord-1004486-f1ie5j7q authors: Wilkins, Hannah; Jastaniah, Ebaa; Spray, Beverly; Forrest, James C.; Boehme, Karl W.; Kirkpatrick, Catherine; Boyanton, Bobby L.; Spiro, David M.; Crawley, Lee; Quang, Lawrence; Kennedy, Joshua L. title: Seroprevalence of SARS‐CoV‐2 antibodies in front‐line pediatric health care workers date: 2022-05-16 journal: J Am Coll Emerg Physicians Open DOI: 10.1002/emp2.12743 sha: 83349fc94f08b287f9f866161e55bd5c30713ce6 doc_id: 1004486 cord_uid: f1ie5j7q 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. 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. COVID, COVID-19, healthcare workers, pediatric emergency department, SARS-CoV-2 antibodies, vaccine response INTRODUCTION As the global SARS-CoV-2 pandemic progressed, it became clear that health care workers (HCWs) were at risk for infection due to workplace exposures. Seroprevalence studies indicate that emergency department (ED) and other front-line HCWs have an increased infection risk that is nearly equivalent to those working in dedicated COVID-19 units; however, the risk can vary by region. 1, 2 One study of emergency medicine attending physicians, resident physicians, and physician assistants at a high-volume ED found a seroconversion rate of 46%, which was more than twice the estimated community seroprevalence. 3 Little is known about the risks of SARS-CoV-2 exposure for pediatric front-line HCWs. Studies of adult front-line HCWs may not be generalizable to pediatric HCWs for several reasons. First, adult and pediatric ED visits sharply declined during the pandemic and remained below prior years' baseline for several months, but the decline among pediatric ED visits was more significant and prolonged than for adult visits. 4 Additionally, children might be less likely to transmit the virus than adults. 5 Together, these factors could lower the risk for pediatric HCWs compared to their adult counterparts. Conversely, it is also possible that the higher rate of mild or asymptomatic infections in children 6 could lead to more opportunities for pediatric frontline HCW exposures, especially in situations where full personal protective equipment was conserved for use with symptomatic patients. Also, very young children or those with special needs may not be able to safely comply with masking guidelines that could increase pediatric HCW exposures, even in the absence of high-risk aerosol-generating procedures. A better understanding of the exposure risks specific for pediatric ED HCWs would help inform staffing decisions and future screening methods, potentially protecting not only HCWs themselves but also their more vulnerable patients. This study aims to determine the seroprevalence of SARS-CoV-2 antibodies in front-line HCWs employed at a large pediatric tertiary care ED. Because SARS-CoV-2 vaccines became available during the enrollment period, secondary goals were to compare the serologic profiles of those with and without vaccination and determine a role for multiantigen antibody screening. Volunteers were recruited between October 2020 and April 2021 from After enrollment, participants were provided a questionnaire requesting basic demographic information; underlying medical condition(s); COVID-19 symptom(s) in the last 6 months, last 2 months, and/or last The primary outcome of this study is to determine the presence or absence of SARS-CoV-2 antibodies in pediatric front-line health care workers. Venipuncture was performed on all subjects after completion of the informed consent. One BD Vacutainer® serum separator tube (Becton Dickinson, Franklin Lakes, NJ, USA) per participant was filled and centrifuged for serum per manufacturer's instructions. Serum was aliquoted and stored at -80 • C until antibody testing could be performed. A 2-tier enzyme linked immunoabsorbent assay (ELISA) assay was designed and used to evaluate participants' sera for SARS-CoV-2 antibodies, as suggested by the Centers for Disease Control and Prevention guidelines. 7 As previously described, all sera were initially tested for IgG and IgM antibodies to the SARS-CoV-2 receptor binding domain (RBD). Samples scoring positive for RBD binding were confirmed with a 4-antigen confirmation test (FACT). 8, 9 The FACT con- Sensitivity and specificity were 100% and 94.6%, respectively. The raw seroprevalence of SARS-CoV-2 was calculated by determin- Demographic data are represented in Table 1 The questionnaire identified that 3 participants had previously been diagnosed with COVID-19 by PCR before enrollment in the study. These 3 HCWs had symptoms consistent with the diagnosis at least 6 months before enrollment in this study, including fever, cough, and loss of smell. Two were <10 days after first vaccination and 1 was unvaccinated at the time of enrollment. All 3 had antibodies to SARS-CoV-2 RBD, S, and N, which is likely indicative of prior infection because current vaccines should stimulate antibody only to the S protein. The questionnaire also identified subjects who suspected they were exposed to SARS-CoV-2 at work or in the community but were never PCR tested. These subjects also had symptoms consistent with SARS-CoV-2 infection 6 months before enrollment, specifically fever (57%), cough (48%), loss of smell (19%), runny nose/congestion (62%), headache (62%), and nausea, vomiting, and diarrhea (52%). Eight of these subjects had received at least 1 dose of vaccine at enrollment with only 1 receiving both vaccinations. In these subjects, we found that 42.8% (9/21) had antibodies to S and 23.8% (5/21) had N-specific antibodies. The small sample size limits the power of our study and the inferences that can be drawn from the data. This is most obvious (eg, the wide CI) We found that 14% of our sample of pediatric ED HCWs who were unvaccinated or <10 days from first vaccine dose had antibodies to SARS-CoV-2 approximately 11 months after the start of the pandemic. F I G U R E 1 Seroprevalence of SARS-CoV-2 antibodies for front-line pediatric health care workers in Arkansas As expected, vaccine administration was associated with increased antibodies to S and RBD. However, this was evident only if the participant was ≥10 days after their first vaccination. We found that 6 of 7 (86%) participants who were ≥10 days after first vaccination had antibodies. Antibodies to SARS-CoV-2 were found in only 22.2% of those <10 days from first vaccination, suggesting care should be taken for exposures to the virus during this time. Further, our study suggests the use of a multiantigen screen to possibly discriminate between those with natural and vaccine acquired immunity. N antibodies were found in many enrollees who had previously tested positive by PCR for SARS-CoV-2, a response that would not be expected with vaccination. Despite working in a high-risk environment, our small sampling indicates that pediatric front-line HCWs had a low seroprevalence of SARS-CoV-2 antibodies. Seroprevalence of SARS-CoV-2 antibodies and associated factors in healthcare workers: a systematic review and meta-analysis Seroprevalence of SARS-CoV-2 IgG antibodies among health care workers prior to vaccine administration in Europe, the USA and East Asia: A systematic review and meta-analysis COVID-19 Seroconversion in Emergency Professionals at an Urban Academic Emergency Department in New York City The role of children in the transmission of SARS-CoV2: updated rapid review Characterizing pediatric emergency department visits during the COVID-19 pandemic Coronavirus Disease 2019 Case Surveillance -United States Interim Guidelines for CoVID-19 Antibody Testing 2020 Temporal Variations in Seroprevalence of SARS-CoV-2 Infections by Race and Ethnicity in Arkansas. medRxiv Pediatric SARS-CoV-2 seroprevalence in Arkansas over the first year of the COVID-19 pandemic A population-based analysis of the longevity of SARS-CoV-2 antibody seropositivity in the United States MD, is an Assistant Professor in the Division of Pediatric Emergency Medicine at University for Arkansas for Seroprevalence of SARS-CoV-2 antibodies in front-line pediatric health care workers The authors have none to disclose.