Update Alert 2: Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community Settings
Authors: Roger Chou, Tracy Dana, Rebecca Jungbauer, Chandler Weeks, Marian S. McDonagh
Journal: Annals of Internal Medicine (2020)

Letters27 August 2020Update Alert 2: Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community SettingsFREERoger Chou, MD, Tracy Dana, MLS, Rebecca Jungbauer, DrPH, Chandler Weeks, MPH, and Marian S. McDonagh, PharmDRoger Chou, MDPacific Northwest Evidence-based Practice Center and Oregon Health & Science University, Portland, Oregon (R.C., T.D., R.J., C.W., M.S.M.)Search for more papers by this author, Tracy Dana, MLSPacific Northwest Evidence-based Practice Center and Oregon Health & Science University, Portland, Oregon (R.C., T.D., R.J., C.W., M.S.M.)Search for more papers by this author, Rebecca Jungbauer, DrPHPacific Northwest Evidence-based Practice Center and Oregon Health & Science University, Portland, Oregon (R.C., T.D., R.J., C.W., M.S.M.)Search for more papers by this author, Chandler Weeks, MPHPacific Northwest Evidence-based Practice Center and Oregon Health & Science University, Portland, Oregon (R.C., T.D., R.J., C.W., M.S.M.)Search for more papers by this author, and Marian S. McDonagh, PharmDPacific Northwest Evidence-based Practice Center and Oregon Health & Science University, Portland, Oregon (R.C., T.D., R.J., C.W., M.S.M.)Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/L20-1067 SectionsSupplemental MaterialAboutVisual AbstractPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail This is the second monthly update alert for a living rapid review on the use of masks for prevention of respiratory virus infections, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in health care and community settings (1). Searches were updated from 3 July 2020 to 2 August 2020 using the same search strategies as the original review, except that inclusion was restricted to peer-reviewed studies. The updated searches identified 286 citations. One study on masks for prevention of SARS-CoV-2 infection in a health care setting was added for this update (Supplement Tables 1 to 3) (2); the original review and prior update had no studies on masks for prevention of SARS-CoV-2 infection.The new case–control study was done in India. It evaluated 378 health care workers infected with SARS-CoV-2 and 373 uninfected health care worker controls using data drawn from a national database registry of health care workers undergoing SARS-CoV-2 testing (2). The study found that any mask use (mask type not specified) was associated with a lower risk for SARS-CoV-2 infection compared with no mask use (unadjusted odds ratio, 0.35 [95% CI, 0.22 to 0.57]). However, mask use was not retained in the multivariable model. The study was susceptible to recall bias. In addition, 40% of eligible cases were not included in the study and attrition was not reported. Given these limitations, the strength of evidence on mask use versus no use in health care settings and risk for SARS-CoV-2 infection was assessed as insufficient (Supplement Table 4).No new studies evaluated the effects of mask use and risk for SARS-CoV-2 infection in community settings or the effects of mask use and risk for SARS-CoV-1 infection, Middle East respiratory syndrome-CoV infection, or influenza or influenza-like illness. There were no new studies on the effectiveness and safety of mask reuse or extended use. We plan the next update in 2 months.References1. Chou R, Dana T, Jungbauer R, et al. Masks for prevention of respiratory virus infections, including SARS-CoV-2, in health care and community settings. A living rapid review. Ann Intern Med. 2020;173:542-55. [PMID: 32579379]. doi:10.7326/M20-3213 LinkGoogle Scholar2. Chatterjee P, Anand T, Singh KJ, et al. Healthcare workers & SARS-CoV-2 infection in India: a case-control investigation in the time of COVID-19. Indian J Med Res. 2020;151:459-467. [PMID: 32611916] doi:10.4103/ijmr.IJMR_2234_20 CrossrefMedlineGoogle Scholar Comments 0 Comments Sign In to Submit A Comment Author, Article, and Disclosure InformationAuthors: Roger Chou, MD; Tracy Dana, MLS; Rebecca Jungbauer, DrPH; Chandler Weeks, MPH; Marian S. McDonagh, PharmDAffiliations: Pacific Northwest Evidence-based Practice Center and Oregon Health & Science University, Portland, Oregon (R.C., T.D., R.J., C.W., M.S.M.)Disclaimer: The authors of this manuscript are responsible for its content. Statements in the manuscript do not necessarily represent the official views of or imply endorsement by the Agency for Healthcare Research and Quality or the U.S. Department of Health and Human Services.Financial Support: By the Agency for Healthcare Research and Quality (contract HHSA290201500009I, task order 75Q80119F32021).Disclosures: Disclosures can be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=L20-1067.Corresponding Author: Roger Chou, MD, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Mail Code BICC, Portland, OR 97239; e-mail, chour@ohsu.edu.This article was published at Annals.org on 27 August 2020. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetailsSee AlsoUpdate Alert: Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community Settings Roger Chou , Tracy Dana , Rebecca Jungbauer , Chandler Weeks , and Marian S. McDonagh Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community Settings Roger Chou , Tracy Dana , Rebecca Jungbauer , Chandler Weeks , and Marian S. McDonagh Update Alert 3: Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community Settings Roger Chou , Tracy Dana , Rebecca Jungbauer , and Chandler Weeks Update Alert 4: Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community Settings Roger Chou , Tracy Dana , Rebecca Jungbauer , and Chandler Weeks Update Alert 5: Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community Settings Roger Chou , Tracy Dana , Rebecca Jungbauer , and Chandler Weeks Update Alert 6: Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community Settings Roger Chou , Tracy Dana , and Rebecca Jungbauer Update Alert 7: Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community Settings Roger Chou , Tracy Dana , Rebecca Jungbauer Update Alert 8: Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community Settings Roger Chou , Tracy Dana , Rebecca Jungbauer Major Update: Masks for Prevention of SARS-CoV-2 in Health Care and Community Settings—Final Update of a Living, Rapid Review Roger Chou , and Tracy Dana Metrics Cited byUpdate Alert 8: Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community SettingsRoger Chou, MD, Tracy Dana, MLS, Rebecca Jungbauer, DrPHUpdate Alert 7: Masks for Prevention of Respiratory Virus Infections, Including SARS-CoV-2, in Health Care and Community SettingsRoger Chou, MD, Tracy Dana, MLS, Rebecca Jungbauer, DrPHMasks and Face Coverings for the Lay Public A Narrative UpdateThomas Czypionka, MD, Trisha Greenhalgh, PhD, Dirk Bassler, PhD, and Manuel B. Bryant, PhD 6 October 2020Volume 173, Issue 7 Page: 132 Keywords COVID-19 Disclosure Health care Health care providers Odds ratio Prevention, policy, and public health Respiratory infections Safety Safety studies Upper respiratory tract infections ePublished: 27 August 2020 Issue Published: 6 October 2020 PDF downloadLoading ...