Several references provide estimates of the proportion of HCW infected with SARS-CoV2 that range from 0.9% -20%. A recent review from Alberta Health Services that examined the COVID-19 rt-PCR test results among HCW indicates that in that province 2.4% of physicians and 0.9% of non-MD HCW who were tested were positive for SARS-CoV-2 compared to 3.5% of the general population.
In the studies reviewed, the majority of cases are confirmed by RT-PCR, while only one reference also used serology testing.
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Badea, A; Groot G; Dalidowicz, M; Young, C; Miller, L. What are the recommendations around settling times following aerosol generating procedures on suspected or confirmed COVID-19 patients? 2020 Dec 1; Document no.: EOC081401v2 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2020. 24 p. (CEST rapid review report)