Alliance for Pandemic Preparedness
October 30, 2020
Association of County-Wide Mask Ordinances with Reductions in Daily CoVID-19 Incident Case Growth in a Midwestern Region Over 12 Weeks
Category: Article Summary
Topic: Non-Pharmaceutical Interventions
Keywords (Tags): masks, non-pharm interventions
- [Pre-print, not peer-reviewed] Missouri counties with mask mandates had a daily percent COVID-19 growth rate that was 32% lower than the growth rate in counties without mask mandates, based on a population-based quasi-experimental longitudinal study conducted from June to September. In the 3 weeks before mandatory mask mandates were instated, the average daily percent increase in incident COVID-19 cases was similar across all counties (0.9% vs. 1.3%). At 12 weeks post-mask mandate, the average daily COVID-19 case growth in counties with no mandate was 2.4%, which was significantly higher than the average daily COVID case growth among counties with a mandate (1.4%). Following implementation of mask mandates, disparities in infection rate by race and population density were no longer significant.
Shacham et al. (Oct 30, 2020). Association of County-Wide Mask Ordinances with Reductions in Daily CoVID-19 Incident Case Growth in a Midwestern Region Over 12 Weeks. Pre-print downloaded Oct 30 from https://doi.org/10.1101/2020.10.28.20221705