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Association of Elementary School Reopening Status and County COVID-19 Incidence
Kenneth A Michelson1, Margaret E Samuels-Kalow2
1Division of Emergency Medicine, Boston Children's Hospital (KA Michelson), Boston, Mass.
Objective:
To examine the association between elementary school opening status (ESOS) and changes in pediatric COVID-19 incidence.
Methods:
We conducted a cross-sectional study of US counties with school districts with ≥500 elementary school students. The main exposure was ESOS in September, 2020. The outcome was county incidence of COVID-19. Age-stratified negative binomial regression models were constructed using county adult COVID-19 incidence.
Results:
Among 3220 US counties, 618 (19.2%) were remote, 391 (12.1%) were hybrid, 2022 (62.8%) were in-person. In unadjusted models, COVID-19 incidence after school started was higher among children in hybrid or in-person counties compared with remote counties. After adjustment for local adult incidence, among children aged 0 to 9, the incidence rate ratio of COVID-19 (IRR) compared with remote counties was 1.01 (95% confidence interval [CI] 0.93-1.08) in hybrid counties and 0.79 (95% CI 0.75-0.84) in in-person counties.
Conclusions:
Counties with in-person learning did not have higher rates of COVID-19 after adjustment for local adult rates.
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