Researchers in the United States have conducted an analysis suggesting that students returning to university campuses this fall (2020) may have increased the number of new cases of coronavirus disease 2019 (COVID-19) within surrounding areas.
The team’s analysis of publicly available county-level data found that the mean number of daily COVID-19 cases increased between September 1st and October 22nd, compared with during August.
Brahmajee Nallamothu and colleagues from the University of Michigan also found that compared with holding classes in person, conducting them online or partially online was associated with the reduced spread of the virus.
The researchers say the findings could guide policies regarding the reopening of universities in upcoming semesters.
“These findings could help public health officials consider policies to mitigate additional waves of infection during the upcoming winter,” they write.
Regions with universities and colleges can expect a surge in COVID-19 cases during the first few weeks of students returning to campus, advises the team. Supplies of facemasks and medication, as well as strict social distancing policies should be arranged in advance to help mitigate spread, they add.
The researchers also say that holding virtual classes online or partially online may help to reduce the number of new cases.
A pre-print version of the paper is available on the medRxiv* server while the article undergoes peer review.
The research illustrates how to calculate our exposure variables using our state of Michigan. Left: The percentile rank of the mean daily confirmed cases from September 1st to October 22nd relative to all counties in the U.S. Middle: Schematic illustration of how to construct the main exposure variables in our analysis of U.S. counties with universities and colleges: the proportion of enrollment for three policies within each county. Right: The geographic distribution of universities’ reopening policies over counties in Michigan
*Important notice: medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.
The effects of students returning to campus have been uncertain
In the United States, the new academic year for universities and colleges began during the midst of the COVID-19 pandemic - in late august and early September this year.
Following the closure of campuses in March and April, many institutions reopened during the fall, while others opted to hold classes online or to use a partially online “hybrid” approach.
Although institutions have adopted many measures to try to ensure reopening is safe, multiple media reports have suggested outbreaks of COVID-19 in universities and colleges that have extended to local communities.
“Despite such anecdotal observations, the precise effects of students returning to campus on their local regions remain uncertain,” writes Nallamothu and colleagues. “Furthermore, how specific university and college reopening policies may be linked to the spread of coronavirus is still unclear.”
What did the researchers do?
The team used several publicly available data sources to examine the association between the number of students returning to campus and the number of county-level new cases of COVID-19 since September 1st.
The study covered 2,893 counties, of which 1,069 were home to at least one college or university.
The researchers also studied how different reopening policies (online, hybrid and in-person) correlated with new confirmed COVID-19 cases in the local region.
What did they find?
The mean number of daily confirmed cases per 10,000 county population increased from 1.51 between August 1st and August 31st to a mean of 1.98 between September 1st and October 22nd.
A trend in the overall number of daily new confirmed cases across the United States also started to increase from early September.
The mean proportion of students returning to university and college was 2.1% of the county population.
Multivariate regression analysis showed that counties with higher proportions of in-person or hybrid university enrollment were associated with higher rates of new COVID-19 cases within the local region.
For every 10% rise in the ratio of in-person or hybrid enrollment to the county population, the mean number of new COVID-19 cases would increase by about 42 cases per 30 days in a median-size county where at least one university was located, says the team.
Compared with holding classes in person, conducting classes online or in hybrid mode was negatively associated with new COVID-19 cases.
The findings could help to inform guidance for upcoming semesters
Nallamothu and colleagues say the findings could help to inform guidance on the upcoming winter/spring 2021 semesters.
For example, regions with universities and colleges should expect a spike in confirmed cases within the first few weeks of students returning to campus.
“Medical supplies such as masks and medication should be prepared in advance as well as enforcement of strict social distancing,” they advise.
“In addition, for those areas that do choose to reopen, we found evidence to support that an online or hybrid mode with virtual classes may be the preferable option at mitigating the number of new confirmed COVID-19 cases,” concludes the team.
*Important notice: medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.
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