182: Prevalence of Coronavirus Antibody Among 764 Frontline Healthcare Workers at an Academic Hospital

INTRODUCTION: The ongoing coronavirus disease (COVID-19) pandemic has a major impact on frontline health care workers Scarce personal protective equipment (PPE) has forced hospitals to conserve and reuse some of their PPE The efficacy of these practices in preventing transmission of COVID-19 from patients to health care workers is unclear There are limited data on the prevalence of antibodies specific for COVID-19 exposure among health care workers Our objective was to determine the prevalence of positive immunoglobulin G antibody specific to COVID-19 in frontline healthcare workers at University Medical Center (UMC) and Texas Tech University Health Sciences Center in Lubbock, Texas METHODS: Blood samples were collected on 764 asymptomatic healthcare workers at University Medical Center and Texas Tech University Health Sciences Center, Lubbock, Texas, after informed consents were signed IgG antibody to SARS-CoV-2 was measured using Abbott's SARS-CoV-2 IgG Reagent Kit in combination with the SARSCoV- 2 IgG Calibrator Kit on the ARCHITECT i1000SR analyzer RESULTS: The prevalence of IgG specific antibodies to COVID-19 was 0 8% Six of the 764 participants tested positive Three of the six participants with positive results had prior COVID-19 diagnosis with mild symptoms managed at home The other three had asymptomatic infection CONCLUSIONS: The prevalence of IgG specific antibodies to COVID-19 was much lower than expected in our study population despite high sensitivity and specificity of the test reagent Possible explanations for this include adequate PPE measures, low COVID-19 infection in Lubbock, Texas, inadequate time for IgG response, and possible clearance of COVID-19 infection locally by the respiratory tract defense system without eliciting a systemic immunologic response