Background Asymptomatic severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections are well documented Healthcare workers (HCW) are at increased risk of infection due to occupational exposure to infected patients We aim to determine the prevalence of SARS-CoV-2 antibodies among HCW who did not come to medical attention Methods We prospectively recruited 400 HCW from the National Public Health Laboratory and two COVID-19 designated public hospitals in Klang Valley, Malaysia between 13/4/2020 and 12/5/2020 Quota sampling was used to ensure representativeness of HCW involved in direct and indirect patient care All participants answered a self-administered questionnaire and blood samples were taken to test for SARS-CoV-2 antibodies by surrogate virus neutralization test Findings The study population comprised 154 (38 5%) nurses, 103 (25 8%) medical doctors, 47 (11 8%) laboratory technologists and others (23 9%) A majority (68 9%) reported exposure to SARS-CoV-2 in the past month within their respective workplaces Adherence to personal protection equipment (PPE) guidelines and hand hygiene were good, ranging from 91-100% compliance None (95% CI: 0, 0 0095) of the participants had SARS-CoV-2 antibodies detected, despite 182 (45 5%) reporting some symptoms one month prior to study recruitment One hundred and fifteen (29%) of participants claimed to have had contact with known COVID-19 persons outside of their workplace Interpretation Zero seroprevalence among HCW suggests a low incidence of undiagnosed COVID-19 infection in our healthcare setting during the first local wave of SARS-CoV-2 infection The occupational risk of SARS-CoV-2 transmission within healthcare facilities can be prevented by adherence to infection control measures and appropriate use of PPE
Serology surveillance of SARS-CoV-2 antibodies among healthcare workers in COVID-19 designated facilities in Malaysia