Association of Elementary School Reopening Status and County COVID-19 Incidence

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.