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Editorial
. 2020 Sep 15;173(6):489-491.
doi: 10.7326/M20-2567. Epub 2020 May 22.

Cloth Masks May Prevent Transmission of COVID-19: An Evidence-Based, Risk-Based Approach

Catherine M Clase  1 , Edouard L Fu  2 , Meera Joseph  1 , Rupert C L Beale  3 , Myrna B Dolovich  1 , Meg Jardine  4 , Johannes F E Mann  5 , Roberto Pecoits-Filho  6 , Wolfgang C Winkelmayer  7 , Juan J Carrero  8
Affiliations
Editorial

Cloth Masks May Prevent Transmission of COVID-19: An Evidence-Based, Risk-Based Approach

Catherine M Clase et al. Ann Intern Med. .

Abstract

As the COVID-19 pandemic progressed across the world, governments, international agencies, policymakers, and public health officials began recommending widespread use of nonmedical cloth masks to reduce the transmission of SARS-CoV-2. The authors of this article suggest that there is convincing evidence to support this recommendation.

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Figures

Figure.
Figure.
Definitions of and relationship among FE, PF, and TIL. For consistency, we calculated FE from data provided in the original work rather than presenting the data in the units chosen by the authors. PF and fit factor are synonyms. FE = filtration efficiency; PF = protection factor; TIL = total inward leakage.
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References

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