Effectiveness of Adding a Mask Recommendation to Other Public Health Measures
Authors: Carl Llor
Journal: Annals of Internal Medicine (2021)

LettersAugust 2021Effectiveness of Adding a Mask Recommendation to Other Public Health MeasuresFREECarl Llor, MD, PhDCarl Llor, MD, PhDUniversity Institute in Primary Care Research Jordi Gol, Via Roma Health Centre, Barcelona, Spain, and University of Southern Denmark, Odense, DenmarkAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/L21-0399 SectionsAboutVisual AbstractPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail TO THE EDITOR: Bundgaard and colleagues' randomized controlled trial (1) showed that face mask use supplementing other public health strategies did not significantly reduce SARS-CoV-2 infection in mask wearers. The authors themselves mention several limitations of their study, mainly low adherence to mask wearing and lack of assessment of whether masks could decrease disease transmission from mask wearers to others. However, other variables may make generalization of these results difficult. The randomized controlled trial design is irrefutably the best method in clinical research addressing interventions, and we applaud the authors for doing such an important trial in a short period of time. Still, this trial was done in a country with a low-moderate incidence of COVID-19 and during lockdown (April and May 2020).Persons in many other areas are less likely to avoid public places and stay home than residents of Denmark. Social distancing could qualify as an oxymoron in Southern Europe, South America, the United States, and many other crowded parts of the world. In such places, walking arm in arm with friends; eating in crowded restaurants and terraces; or kissing relatives, neighbors, and friends are part of the culture. Solid evidence now shows that persons in poor health are more susceptible to serious illnesses (2). For example, in Southern Europe, low-paid employees are less likely to do their jobs from home, and taking public transport to crowded workplaces and families being pushed into housing with insufficient space might lead to more contagions.The "real-life" conditions in many areas of the world differ substantially from those in Denmark. We should ask whether the modest protection from infection with SARS-Cov-2 experienced by mask wearers in that country would have been the same if Bundgaard and colleagues' trial had been done in crowded areas with no curfew. We agree with the authors that more well-conducted studies are needed before drawing such a conclusion.References1. Bundgaard H, Bundgaard JS, Raaschou-Pedersen DET, et al. Effectiveness of adding a mask recommendation to other public health measures to prevent SARS-CoV-2 infection in Danish mask wearers. A randomized controlled trial. Ann Intern Med. 2021;174:335-43. [PMID: 33205991]. doi:10.7326/M20-6817 LinkGoogle Scholar2. Marmot M. Social determinants of health inequalities. Lancet. 2005;365:1099-104. [PMID: 15781105] CrossrefMedlineGoogle Scholar Comments0 CommentsSign In to Submit A Comment Author, Article, and Disclosure InformationAffiliations: University Institute in Primary Care Research Jordi Gol, Via Roma Health Centre, Barcelona, Spain, and University of Southern Denmark, Odense, DenmarkDisclosures: Disclosures can be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=L21-0399. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetailsSee AlsoEffectiveness of Adding a Mask Recommendation to Other Public Health Measures to Prevent SARS-CoV-2 Infection in Danish Mask Wearers Henning Bundgaard , Johan Skov Bundgaard , Daniel Emil Tadeusz Raaschou-Pedersen , Christian von Buchwald , Tobias Todsen , Jakob Boesgaard Norsk , Mia M. Pries-Heje , Christoffer Rasmus Vissing , Pernille B. Nielsen , Ulrik C. Winsløw , Kamille Fogh , Rasmus Hasselbalch , Jonas H. Kristensen , Anna Ringgaard , Mikkel Porsborg Andersen , Nicole Bakkegård Goecke , Ramona Trebbien , Kerstin Skovgaard , Thomas Benfield , Henrik Ullum , Christian Torp-Pedersen , and Kasper Iversen Effectiveness of Adding a Mask Recommendation to Other Public Health Measures Janet Rand Effectiveness of Adding a Mask Recommendation to Other Public Health Measures Henning Bundgaard , Anna K. Ringgaard , Daniel Emil Tadeusz Raaschou-Pedersen , Johan Skov Bundgaard , and Kasper K. Iversen Effectiveness of Adding a Mask Recommendation to Other Public Health Measures Hans Gaines Effectiveness of Adding a Mask Recommendation to Other Public Health Measures Matthew A. Spinelli , David V. Glidden , Efstathios D. Gennatas , George W. Rutherford , and Monica Gandhi Effectiveness of Adding a Mask Recommendation to Other Public Health Measures Brendan Moran Metrics August 2021Volume 174, Issue 8Page: 1194-1194 ePublished: 17 August 2021 Issue Published: August 2021 Copyright & PermissionsCopyright © 2021 by American College of Physicians. All Rights Reserved.PDF downloadLoading ...