Association Between K–12 School Mask Policies and School-Associated COVID-19 Outbreaks — Maricopa and Pima Counties, Arizona, July–August 2021
Open accessAbstract
CDC recommends universal indoor masking by students, staff members, faculty, and visitors in kindergarten through grade 12 (K-12) schools, regardless of vaccination status, to reduce transmission of SARS-CoV-2, the virus that causes COVID-19 (1). Schools in Maricopa and Pima Counties, which account for >75% of Arizona's population (2), resumed in-person learning for the 2021-22 academic year during late July through early August 2021. In mid-July, county-wide 7-day case rates were 161 and 105 per 100,000 persons in Maricopa and Pima Counties, respectively, and 47.6% of Maricopa County residents and 59.2% of Pima County residents had received at least 1 dose of a COVID-19 vaccine. School districts in both counties implemented variable mask policies at the start of the 2021-22 academic year (Table). The association between school mask policies and school-associated COVID-19 outbreaks in K-12 public noncharter schools open for in-person learning in Maricopa and Pima Counties during July 15-August 31, 2021, was evaluated.
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With prioritization of older age groups for vaccination, school-age children now account for an increasing proportion of cases and hospitalizations compared with their proportion early in the pandemic, and school outbreaks are occurring.
“With the prioritization of older age groups for vaccination, school-age children now account for an increasing proportion of cases and hospitalizations as compared with their proportion early in the pandemic,10,22,23,24 and school outbreaks are occurring.14,25”
From Evaluation of the BNT162b2 Covid-19 Vaccine in Children 5 to 11 Years of Age (2022) · cites this paper as [25]
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- Authors
- Jehn, M., McCullough, J. M., Dale, A. P., Gue, M., Eller, B., Cullen, T., & Scott, S. E.
- Affiliations
- Pima County Health Department (US)
- Corresponding author
- Jehn, Megan
- Venue
- MMWR. Morbidity and Mortality Weekly Report
- Published
- 2021-10-01
- Volume
- 70
- Issue
- 39
- Pages
- 1372-1373
- ISSN
- 0149-2195 (ISSN-L)
- 1545-861X
- PMC
- PMC8486387
- OpenAlex
- W3202262344
- Cited by
- 79
- References
- 1
- Citations by year
- 2026: 1 · 2025: 5 · 2024: 10 · 2023: 18 · 2022: 38 · 2021: 7
- FWCI
- 7.06
- Type
- journal article
- Language
- en
- Open access
- diamond
- doi.org
- Locations
- MMWR Morbidity and Mortality Weekly Report (publishedVersion)
- Europe PMC (PubMed Central) (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Topics
- Physical Sciences › Mathematics › Modeling and Simulation › COVID-19 epidemiological studies
- Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
- Social Sciences › Education › Education during COVID-19 pandemic
- Keywords
- COVID-19 pandemic, SARS-CoV-2, K-12 schools, in-person learning, school closures, Maricopa County, Pima County, COVID-19 vaccination
- MeSH terms
- COVID-19, Adolescent, Arizona, Child, Child, Preschool, Disease Outbreaks, Humans, Masks, Schools, Organizational Policy
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