Community-level face mask usage in Boston, MA

SummaryWhat is already known about this topic?Community-level face mask use is encouraged as an important preventive measure against COVID-19 transmission, and evidence suggests that jurisdictions which implement face mask mandates see a subsequent decline in COVID incidence.What is added by this report?In the Greater Boston area when a face mask mandate is in effect, 95% of people observed were wearing some type of face covering. Most of which were wearing fabric/cloth coverings (51%) or single use surgical masks (40%). Of those wearing a face covering, 85% were appropriately fitted. Indoor locations have higher adherence of appropriately worn face masks, compared to outdoor locations.What are the implications for public health practice?Adherence with face mask mandates was very high, but many individuals wore fabric face masks with unknown filtration efficacy. In addition, it was common for individuals to mis-wear, adjust, or remove their masks. Public health policies requiring mask use should include messaging about appropriate type and best practices for use.