Objectives: We aimed to compare the prevalence of asymptomatic coronavirus disease 19 (COVID-19) among clinical staff in designated COVID-19 units versus that among staff in similar units with no known or suspected COVID-19 patients. Methods: We conducted a cross-sectional survey of healthcare workers (HCWs) in eight Israeli general hospitals. The survey involved a questionnaire and a PCR test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We surveyed HCWs in COVID-19 units and comparison units (internal medicine and cardiology) between 30th April and 7th May 2020. Results: There were 522 participants: 291 from COVID-19 units and 231 from comparison units. Only one participant (0.2%, 95%CI: 0.005e1.1%)dan asymptomatic nurse on a COVID-19 unitdtested positive for SARS-CoV-2. In participating COVID-19 units there were two symptomatic HCWs with confirmed COVID- 19 in the 2 weeks before the survey; both were infected by contact with a co-worker outside of the COVID-19 unit. Conclusions: The low prevalence of asymptomatic COVID-19 among HCWs, coupled with an absence of symptomatic COVID-19 acquired during patient care, suggest that Israel's national guidelines for personal protective equipment, which are consistent with those of the World Health Organization, adequately protect HCWs. Elizabeth Temkin, Clin Microbiol Infect 2021;27:130.e1e130.e4 © 2020 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Elizabeth Temkin ¹, * on behalf of the Healthcare Worker COVID-19 Surveillance Working Group

¹⁾ National Institute for Antibiotic Resistance and Infection Control, Israel Ministry of Health, Israel

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