Association between Implementation of a Universal Face Mask Policy for Healthcare Workers in a Health Care System & SARS-CoV-2 positivity testing rate in Healthcare Workers

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Journal of occupational and environmental medicine


OBJECTIVE: Examine the effect of a universal facemask policy for healthcare workers (HCW) and incidence of SARS-CoV-2 positivity.

METHODS: Daily number of symptomatic HCW tested, SARS-CoV-2 positivity rates, and HCW job-descriptions were collected pre and post Universal HCW facemask policy (March 26). Multiple change point regression was used to model positive-test-rate data. SARS-CoV-2 testing and positivity rates were compared for pre-intervention, transition, post-intervention, and follow-up periods.

RESULTS: Between March 12 - August 10, 2020, 19.2% of HCW were symptomatic for COVID-19 and underwent SARS-CoV-2 testing. A single change point was identified ∼March 28-30 (95% probability). Before the change point, the odds of a tested HCW having a positive result doubled every 4.5-7.5  days. Post-change-point, the odds of a tested HCW having a positive result halved every 10.5-13.5  days.

CONCLUSIONS: Universal facemasks was associated with reducing HCW's risk of acquiring COVID-19.

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ePub ahead of print