{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,23]],"date-time":"2025-12-23T09:34:47Z","timestamp":1766482487926,"version":"3.48.0"},"reference-count":23,"publisher":"Oxford University Press (OUP)","issue":"12","license":[{"start":{"date-parts":[[2025,12,23]],"date-time":"2025-12-23T00:00:00Z","timestamp":1766448000000},"content-version":"vor","delay-in-days":22,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000030","name":"US Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["U01CK000674"],"award-info":[{"award-number":["U01CK000674"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,12,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>K-12 schools are not only educational settings but also hubs of social interaction, making them potential drivers of disease transmission within households and communities. While many existing studies have assessed school masking in relation to in-school transmission, the broader community impact of mandatory school masking policies on SARS-CoV-2 infection rates remains poorly understood.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a retrospective quasi-experimental study using the synthetic control method to evaluate the association between masking policies and community infection rates during the fall 2021 US school reopening period, when most schools returned to in-person learning but masking policies varied substantially. Analyses accounted for community characteristics prior to reopening and baseline infection rates.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Counties with mandatory school masking experienced significantly lower SARS-CoV-2 infection rates than those without mandates. In the first 9 weeks after reopening, mandatory masking was associated with 820 fewer cases per 100 000 people (95% CI: 444-1185), corresponding to a relative cumulative reduction of 9.4% (95% CI: 7.3%-11.8%). The strength of this association varied by baseline infection rates, population density, and mobility patterns.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Mandatory school masking policies were linked to meaningful reductions in community SARS-CoV-2 transmission and underscore their value as a public health intervention during pandemic surges.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/haschl\/qxaf233","type":"journal-article","created":{"date-parts":[[2025,12,21]],"date-time":"2025-12-21T12:40:52Z","timestamp":1766320852000},"source":"Crossref","is-referenced-by-count":0,"title":["School masking and COVID-19 community transmission: a synthetic control study"],"prefix":"10.1093","volume":"3","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2597-3760","authenticated-orcid":false,"given":"Xianqun","family":"Luan","sequence":"first","affiliation":[{"name":"PolicyLab, Children's Hospital of Philadelphia , Philadelphia, PA 19104 ,","place":["United States"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8224-4281","authenticated-orcid":false,"given":"Brian T","family":"Fisher","sequence":"additional","affiliation":[{"name":"Division of Infectious Disease, Children's Hospital of Philadelphia , Philadelphia, PA 19104 ,","place":["United States"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9566-5600","authenticated-orcid":false,"given":"Susan E","family":"Coffin","sequence":"additional","affiliation":[{"name":"Division of Infectious Disease, Children's Hospital of Philadelphia , Philadelphia, PA 19104 ,","place":["United States"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-8209-3354","authenticated-orcid":false,"given":"David","family":"Rubin","sequence":"additional","affiliation":[{"name":"Office of the President, University of California , Oakland, CA 94607 ,","place":["United States"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Meredith","family":"Matone","sequence":"additional","affiliation":[{"name":"PolicyLab, Children's Hospital of Philadelphia , Philadelphia, PA 19104 ,","place":["United States"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6133-6988","authenticated-orcid":false,"given":"Jing","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Biostatistics, Epidemiology, and Informatics, Perelman School of Medicine, University of Pennsylvania , Philadelphia, PA 19104 ,","place":["United States"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2025,12,23]]},"reference":[{"issue":"6","key":"2025122304313862100_qxaf233-B1","doi-asserted-by":"publisher","first-page":"e2022056687","DOI":"10.1542\/peds.2022-056687","article-title":"School masking policies and secondary SARS-CoV-2 transmission","volume":"149","author":"Boutzoukas","year":"2022","journal-title":"Pediatrics"},{"issue":"21","key":"2025122304313862100_qxaf233-B2","doi-asserted-by":"publisher","first-page":"1935","DOI":"10.1056\/NEJMoa2211029","article-title":"Lifting universal masking in schools\u2014COVID-19 incidence among students and staff","volume":"387","author":"Cowger","year":"2022","journal-title":"N Engl J Med."},{"issue":"10","key":"2025122304313862100_qxaf233-B3","doi-asserted-by":"publisher","first-page":"384","DOI":"10.15585\/mmwr.mm7110e1","article-title":"SARS-CoV-2 incidence in K\u201312 school districts with mask-required versus mask-optional policies\u2014Arkansas, August\u2013October 2021","volume":"71","author":"Donovan","year":"2022","journal-title":"MMWR Morb Mortal Wkly Rep."},{"issue":"Supplement_2","key":"2025122304313862100_qxaf233-B4","doi-asserted-by":"publisher","first-page":"e2021054268l","DOI":"10.1542\/peds.2021-054268I","article-title":"Masking adherence in K\u201312 schools and SARS-CoV-2 secondary transmission","volume":"149","author":"Moorthy","year":"2022","journal-title":"Pediatrics"},{"key":"2025122304313862100_qxaf233-B5","author":"Camera"},{"issue":"4","key":"2025122304313862100_qxaf233-B6","doi-asserted-by":"publisher","first-page":"e238300","DOI":"10.1001\/jamanetworkopen.2023.8300","article-title":"Association of in-person vs virtual education with community COVID-19 case incidence following school reopenings in the first year of the COVID-19 pandemic","volume":"6","author":"Matone","year":"2023","journal-title":"JAMA Netw Open."},{"key":"2025122304313862100_qxaf233-B7","author":"USAFacts"},{"key":"2025122304313862100_qxaf233-B8","author":"United States Census Bureau"},{"key":"2025122304313862100_qxaf233-B9","author":"Country Health Rankings & Roadmaps"},{"key":"2025122304313862100_qxaf233-B10","author":"ATSDR"},{"key":"2025122304313862100_qxaf233-B11","author":"Google"},{"key":"2025122304313862100_qxaf233-B12","author":"CDC"},{"issue":"7","key":"2025122304313862100_qxaf233-B13","doi-asserted-by":"crossref","first-page":"e1814","DOI":"10.1093\/cid\/ciaa1729","article-title":"County-level predictors of coronavirus disease 2019 (COVID-19) cases and deaths in the United States: what happened, and where do we go from here?","volume":"73","author":"McLaughlin","year":"2021","journal-title":"Clin Infect Dis"},{"issue":"1","key":"2025122304313862100_qxaf233-B14","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1186\/s12889-021-12469-y","article-title":"Association between county-level risk groups and COVID-19 outcomes in the United States: a socioecological study","volume":"22","author":"Khan","year":"2022","journal-title":"BMC Public Health"},{"issue":"7","key":"2025122304313862100_qxaf233-B15","doi-asserted-by":"publisher","first-page":"e2016099","DOI":"10.1001\/jamanetworkopen.2020.16099","article-title":"Association of social distancing, population density, and temperature with the instantaneous reproduction number of SARS-CoV-2 in counties across the United States","volume":"3","author":"Rubin","year":"2020","journal-title":"JAMA Netw Open."},{"key":"2025122304313862100_qxaf233-B16","volume-title":"Pattern Recognition and Machine Learning","author":"Bishop","year":"2006"},{"issue":"1","key":"2025122304313862100_qxaf233-B17","doi-asserted-by":"publisher","first-page":"113","DOI":"10.1257\/000282803321455188","article-title":"The economic costs of conflict: a case study of the Basque Country","volume":"93","author":"Abadie","year":"2003","journal-title":"Am Econ Rev"},{"issue":"490","key":"2025122304313862100_qxaf233-B18","doi-asserted-by":"publisher","first-page":"493","DOI":"10.1198\/jasa.2009.ap08746","article-title":"Synthetic control methods for comparative case studies: estimating the effect of California's tobacco control program","volume":"105","author":"Abadie","year":"2010","journal-title":"J Am Stat Assoc."},{"key":"2025122304313862100_qxaf233-B19","doi-asserted-by":"publisher","first-page":"S26","DOI":"10.1016\/S0140-6736(17)32961-6","article-title":"Use of synthetic control methodology for evaluating public health interventions: a literature review","volume":"390","author":"Bouttell","year":"2017","journal-title":"Lancet"},{"issue":"10","key":"2025122304313862100_qxaf233-B20","doi-asserted-by":"publisher","first-page":"e844","DOI":"10.1016\/S2468-2667(22)00198-0","article-title":"The effect of devolution on health: a generalised synthetic control analysis of Greater Manchester, England","volume":"7","author":"Britteon","year":"2022","journal-title":"Lancet Public Health."},{"issue":"1","key":"2025122304313862100_qxaf233-B21","doi-asserted-by":"publisher","first-page":"209","DOI":"10.1515\/jci-2020-0013","article-title":"When is a match sufficient? A score-based balance metric for the synthetic control method","volume":"8","author":"Parast","year":"2020","journal-title":"J Causal Inference."},{"issue":"3","key":"2025122304313862100_qxaf233-B22","doi-asserted-by":"publisher","first-page":"e1","DOI":"10.1136\/archdischild-2023-326215","article-title":"Child mask mandates for COVID-19: a systematic review","volume":"109","author":"Sandlund","year":"2024","journal-title":"Arch Dis Child."},{"issue":"10","key":"2025122304313862100_qxaf233-B23","doi-asserted-by":"publisher","first-page":"e00691-24","DOI":"10.1128\/spectrum.00691-24","article-title":"School mask policies and SARS-CoV-2 seroprevalence among school-age children\u2014United States, September to December 2021","volume":"12","author":"Nycz","year":"2024","journal-title":"Microbiol Spectr."}],"container-title":["Health Affairs Scholar"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/academic.oup.com\/healthaffairsscholar\/article-pdf\/3\/12\/qxaf233\/66114305\/qxaf233.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/healthaffairsscholar\/article-pdf\/3\/12\/qxaf233\/66114305\/qxaf233.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,23]],"date-time":"2025-12-23T09:31:44Z","timestamp":1766482304000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/healthaffairsscholar\/article\/doi\/10.1093\/haschl\/qxaf233\/8402379"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,12,1]]},"references-count":23,"journal-issue":{"issue":"12","published-print":{"date-parts":[[2025,12,1]]}},"URL":"https:\/\/doi.org\/10.1093\/haschl\/qxaf233","relation":{},"ISSN":["2976-5390"],"issn-type":[{"value":"2976-5390","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2025,12]]},"published":{"date-parts":[[2025,12,1]]},"article-number":"qxaf233"}}