Prevalence of SARS-CoV-2 antibodies among Swiss hospital workers: Results of a prospective cohort study.
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ABSTRACT:
SUBMITTER: Kohler PP
PROVIDER: S-EPMC7582018 | biostudies-literature | 2020 Oct
REPOSITORIES: biostudies-literature
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Prevalence of SARS-CoV-2 antibodies among Swiss hospital workers: Results of a prospective cohort study.
Kohler Philipp P PP Kahlert Christian R CR Sumer Johannes J Flury Domenica D Güsewell Sabine S Leal-Neto Onicio B OB Notter Julia J Albrich Werner C WC Babouee Flury Baharak B McGeer Allison A Kuster Stefan S Risch Lorenz L Schlegel Matthias M Vernazza Pietro P
Infection control and hospital epidemiology 20201008 5
In this prospective cohort of 1,012 Swiss hospital employees, 3 different assays were used to screen serum for SARS-CoV-2 antibodies. Seropositivity was 1%; the positive predictive values of the lateral-flow immunoassay were 64% (IgG) and 13% (IgM). History of fever and myalgia most effectively differentiated seropositive and seronegative participants. ...[more]
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Project description:BackgroundHealthcare workers (HCWs) are a presumed high-risk population for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Identifying factors associated with seroprevalence can help establish better practices in healthcare settings. In this study, we evaluate prevalence of SARS-CoV-2 infection among previously undiagnosed HCWs and describe profiling of antibody responses against SARS-CoV-2, including neutralizing antibodies (NAbs).MethodsWe analyzed a cohort of 386 HCWs in a university hospital in Egypt and 725 volunteers not affiliated to any healthcare facility (non-healthcare workers - NHCWs). Participants provided a nasopharyngeal swab and serum samples for SARS-CoV-2 nucleic acid and SARS-CoV-2-specific antibodies, respectively. HCWs who tested positive by either test were sequentially monitored.ResultsAt baseline, point prevalence of viral carriage was 11.4% in HCWs (n = 44/386) and 11.9% in NHCWs (86/725). The cumulative prevalence of SARS-CoV-2 infection among HCWs considering all studies was 25.6%, which was statistically lower than in NHCWs (41.0%). Prevalence was greatest among janitorial staff (45.9%) and the most affected departments were gastroenterology (31.1%), and emergency medicine (30.0%). Prior anosmia, fever or headache were associated with higher odds of positivity for SARS-CoV-2 infection. Regarding serial antibody measurements, RT-PCR-positive HCWs displayed IgG detection rates of 29.5%, 70% and 60% at visit 1, visit 2 and visit 3, respectively with slow decline of median IgG antibody titers, whereas, corresponding detection rates for total Ig antibodies were 50%, 90.3%, and 88.9%, respectively with increasing median titers. NAbs measured at each time point were positively correlated with total Ig levels, whereas IgG levels were positively correlated with NAbs at visit 1 and visit 3.ConclusionOur results demonstrate lower cumulative prevalence of SARS-CoV-2 infection in HCWs than general population and suggest that asymptomatic HCWs exhibit considerable IgG and total Ig antibodies response as well as NAbs for up to 120 days, with positive correlation in between.
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Project description: Not available
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