Risk of SARS-CoV-2 transmission from universally masked healthcare workers to patients or residents: A prospective cohort study.

In a multifacility prospective cohort study, we identified 116 acute care, 26 long-term care, and 67 rehabilitation patients who received direct care from a universally masked healthcare worker while communicable with COVID-19. Among 133(64%) patients with at least 14-day follow-up, 3 (2.3%, 95% CI, 0.77-6.4) became positive for SARS-CoV-2. Universal masking, embedded with other infection control practices, is associated with low risk of transmission of SARS-CoV-2 from healthcare workers to patients and residents.