School District Prevention Policies and Risk of COVID-19 Among In-Person K-12 Educators, Wisconsin, 2021.

To assess the rate of COVID-19 among in-person K-12 educators and the rate's association with various COVID-19 prevention policies in school districts. We linked actively working, in-person K-12 educators in Wisconsin to COVID-19 cases with onset from September 2 to November 24, 2021. A mixed-effects Cox proportional hazards model, adjusted for pertinent person- and community-level confounders, compared the hazard rate of COVID-19 among educators working in districts with and without specific COVID-19 prevention policies. In-person educators working in school districts that required masking for students and staff experienced 19% lower hazards of COVID-19 than did those in districts without any masking policy (hazard ratio = 0.81; 95% confidence interval = 0.72, 0.92). Reduced COVID-19 hazards were consistent and remained statistically significant when educators were stratified by elementary, middle, and high school environments. In Wisconsin's K-12 school districts, during the fall 2021 academic semester, a policy that required both students and staff to mask was associated with significantly reduced risk of COVID-19 among in-person educators across all grade levels. ( 2022;112(12):1791-1799. https://doi.org/10.2105/AJPH.2022.307095).