Association of University Reopening Policies with New Confirmed COVID-19 Cases in the United States

Importance Reopening of universities in the U.S. has been controversial in the setting of the coronavirus disease 2019 (COVID-19) pandemic. Objective To investigate (1) the association between new COVID-19 cases since September 1st with the number of students returning to campus in each county across the U.S. and (2) how different reopening policies at universities correlated with new COVID-19 cases. Design Observational cohort study using publicly available data sources. Multivariable regression models estimated both effects of university reopening and different reopening policies. Settings and Participants Populations in U.S. counties reporting new confirmed COVID-19 cases from August 1st to October 22nd. Exposures (1) total enrollment of students under the in-person or hybrid policies per county population and (2) proportion of online and hybrid enrollment within each county. Main Outcomes and Measures Mean number of daily new confirmed COVID-19 cases per 10,000 county population from September 1st to October 22nd. Results For 2,893 counties included in the study, mean number of daily confirmed cases per 10,000 county population rose from 1.51 from August 1st to August 31st to 1.98 from September 1st to October 22nd. Mean number of students returning to universities was 2.1% (95% CI, 1.8% to 2.3%) of the county population. The number of students returning to campus had an increased association (β = 2.006, P < 0.001) with new confirmed COVID-19 cases within the local county region where the institution resided. For 1,069 U.S. counties with universities, the mean proportion of online enrollment within each county was 40.1% (95% CI, 37.4% to 42.8%), with most students enrolling in-person or hybrid mode. In comparison to holding classes in-person, reopening universities online (β = -0.329, P < 0.001) or in a hybrid mode (β = -0.272, P = 0.012) had a decreased association with new confirmed COVID-19 cases. Conclusions and Relevance A higher number of students returning to campus in U.S. counties was associated with an increase in new confirmed COVID-19 cases; reopening online or partially online was associated with slower spread of the virus, in comparison to in-person reopening. Question Are students returning to universities and specific reopening policies associated with new confirmed coronavirus cases in United States? Findings In this cohort study of 2,893 U.S. counties, the number of students returning to campus was significantly associated with a higher number of new confirmed COVID-19 cases. In 1,069 U.S. counties with universities, online or hybrid reopening was significantly associated with a lower risk of new cases compared with in-person reopening. Meaning An increased risk of coronavirus infection was seen in surrounding regions after universities reopened last fall, and this effect was largest in those holding in-person classes. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement No external funding was provided to support this manuscript. This work was done through support and access to the American Heart Association COVID-19 Data Challenge Award and its Precision Medicine Platform. Our team was awarded the final prize as part of this competition. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: n/a All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All datasets used are publicly available. Our analysis was conducted using R statistical software version 3.6.0 and 3.6.1. All statistical code is available for replication at https://github.com/yli15/COVID-19-research. .