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. 2022 Jun 1;149(6):e2022056687.
doi: 10.1542/peds.2022-056687.

School Masking Policies and Secondary SARS-CoV-2 Transmission

Angelique E Boutzoukas  1   2 , Kanecia O Zimmerman  1   2   3 , Moira Inkelas  4   5 , M Alan Brookhart  6 , Daniel K Benjamin  7 , Sabrina Butteris  8 , Shawn Koval  9 , Gregory P DeMuri  8 , Vladimir G Manuel  5   10 , Michael J Smith  2 , Kathleen A McGann  2 , Ibukunoluwa C Kalu  2 , David J Weber  11 , Amy Falk  12 , Andi L Shane  13   14 , Jennifer E Schuster  15 , Jennifer L Goldman  15 , Jesse Hickerson  1 , Vroselyn Benjamin  1 , Laura Edwards  1 , Tyler R Erickson  1 , Daniel K Benjamin  1   2   3
Affiliations

School Masking Policies and Secondary SARS-CoV-2 Transmission

Angelique E Boutzoukas et al. Pediatrics. .

Abstract

Objectives: Throughout the COVID-19 pandemic, masking has been a widely used mitigation practice in kindergarten through 12th grade (K-12) school districts to limit within-school transmission. Prior studies attempting to quantify the impact of masking have assessed total cases within schools; however, the metric that more optimally defines effectiveness of mitigation practices is within-school transmission, or secondary cases. We estimated the impact of various masking practices on secondary transmission in a cohort of K-12 schools.

Methods: We performed a multistate, prospective, observational, open cohort study from July 26, 2021 to December 13, 2021. Districts reported mitigation practices and weekly infection data. Districts that were able to perform contact tracing and adjudicate primary and secondary infections were eligible for inclusion. To estimate the impact of masking on secondary transmission, we used a quasi-Poisson regression model.

Results: A total of 1 112 899 students and 157 069 staff attended 61 K-12 districts across 9 states that met inclusion criteria. The districts reported 40 601 primary and 3085 secondary infections. Six districts had optional masking policies, 9 had partial masking policies, and 46 had universal masking. In unadjusted analysis, districts that optionally masked throughout the study period had 3.6 times the rate of secondary transmission as universally masked districts; and for every 100 community-acquired cases, universally masked districts had 7.3 predicted secondary infections, whereas optionally masked districts had 26.4.

Conclusions: Secondary transmission across the cohort was modest (<10% of total infections) and universal masking was associated with reduced secondary transmission compared with optional masking.

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Conflict of interest statement

CONFLICT OF INTERST DISCLOSURES: Angelique Boutzoukas receives salary support through the US government National Institute of Child Health and Human Development T32 training grant (1T32HD094671). Kanecia Zimmerman reports funding from the National Institutes of Health and US Food and Drug Administration. Daniel Benjamin, Jr reports consultancy for Allergan, Melinta Therapeutics, Sun Pharma Advanced Research Co, Ibukun Kalu reports funding from Center for Disease Control Epicenter, Consultancy, Interdisciplinary Professional Education Collaborative Experts and Wayfair. Michael Smith reports being site Coinvestigator for Pfizer adult and pediatric vaccine trials. Dr Brookhart serves on scientific advisory committees for AbbVie, Amgen, Atara Biotherapeutics, Brigham and Women’s Hospital, Gilead, and Vertex. He receives consulting fees and owns equity in NoviSci/Target RWE.

Figures

FIGURE 1
FIGURE 1
Enrollment and subsequent study inclusion. This figure displays the study population, from enrollment through exclusions, to the final study population comprised of 61 school districts: of these, 46 districts consistently universally masked, 9 partially masked, and 6 consistently optionally masked.
FIGURE 2
FIGURE 2
Predicted impact of masking policy on secondary transmission. Predicted impact of masking policy on secondary transmission according to optional masking, partial masking, or universal masking. Actual observations are shown by dots, predicted secondary cases are shown by solid lines, and 95% confidence intervals for the mean predictions are shown by shaded areas.
See this image and copyright information in PMC

Comment in

References

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