HealthDay News — Masks may be associated with a small reduction in the risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in community settings, according to the final update of a living, rapid review published online May 16 in the Annals of Internal Medicine.
Roger Chou, M.D., and Tracy Dana, from Oregon Health & Science University in Portland, updated an evidence synthesis on N95, surgical, and cloth mask effectiveness for preventing SARS-CoV-2 infection in community and health care settings. Data were included from 3 randomized trials and 21 observational studies.
Researchers found that based on 2 randomized trials and 7 observational studies, mask use may be associated with a small reduction in the risk for SARS-CoV-2 infection in community settings compared with no mask use. Surgical masks and N95 respirators may be associated with a similar risk for SARS-CoV-2 infection in routine patient care settings based on 1 new randomized trial with some imprecision and 4 observational studies. Due to methodological limitations and inconsistency, evidence from observational studies was insufficient to assess other mask comparisons.
“As in prior updates, our main finding for community settings was low-to-moderate strength evidence that mask use (any or unspecified type) may be associated with a small reduction in risk for SARS-CoV-2 infection vs no masks,” the authors write.