Background. COVID-19 is an illness caused by a novel coronavirus known as severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2). Laboratory healthcare workers (LHCWs) are at highest risk for COVID-19 infection due to direct exposure to
COVID-19 patients and/or infected samples. Objectives. Our primary objective in this study was to evaluate SARS-CoV-2 Ab
testing as a screening tool for detecting COVID-19 infection among asymptomatic LHCWs. Our secondary aims were to establish
the relationship between exposure to COVID-19 infection and subsequent asymptomatic disease and working in di”erent areas of
the laboratory. Method. e detection of SARS-CoV-2 antibodies was done by di”erent methods (rapid testing, electrochemiluminescence,
and chemiluminescent microparticle immunoassay). e study included 199 asymptomatic LHCWs at
Assiut University Hospital, Egypt, from di”erent laboratory areas including molecular biology, microbiology, parasitology, and
outpatient clinic laboratories in addition to LHCWs involved in automation, phlebotomy, rotating physicians, and those working
in the sample receiving area. Results. e incidence of SARS-CoV-2 antibodies by rapid testing and immunoassay among
asymptomatic LHCWs was 29.6% and 24.4%. Laboratory phlebotomists (55.6%) were most likely to be exposed to positive
patients and samples, followed by those working in the sample receiving area (32%), LHCWs in the automation area (29.6%),
rotating doctors (28.6%), and LHCWs in the diagnostic molecular biology laboratory (15.4%). e sensitivities of the rapid test
and SARS-CoV-2 total antibody were 94.1% and 92%, whereas the speciœcities were 92.6% and 91%. Conclusion. Rapid serological
testing is an e”ective screening method for the detection of SARS-CoV-2 infection among asymptomatic LHCWs and the
identiœcation of the groups of workers who have a signiœcantly higher seroprevalence than the rest of the laboratory population.