CDC: Big in-person universities fueled county COVID spikes last fall

In a new study, the Centers for Disease Control notes higher incidences of the virus in counties during fall 2020 reopening than at those that remained remote.
By: | January 8, 2021
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The Centers for Disease Control on Friday released findings from a study conducted from July through mid-September 2020 that shows counties with large colleges and universities that returned to in-person learning experienced a significant rise in the number of COVID-19 cases over those that didn’t.

Those counties, which include not-for-profit institutions with more than 20,000 students, had a more than 56% increase in case incidence in the 21-day period before and after the resumption of classes began. Those counties where instruction remained remote saw a nearly 18% decline. Counties nationwide with no colleges and universities saw a nearly 6% decline.

“During early August 2020, county-level incidence of coronavirus disease 2019 generally decreased across the United States, compared with incidence earlier in the summer,” the CDC’s researchers noted in the report. “However, among young adults aged 18–22 years, incidence increased. Institutions of higher education have been identified as settings where incidence among young adults increased during August.”

The study, Opening of Large Institutions of Higher Education and County-Level COVID-19 Incidence, highlighted 101 counties across the U.S. that have large universities. The CDC said 78% of institutions in those locales opted for reopening. Those that did experienced a rate of 23.9 cases per 100,000 students, which is among the highest risk for transmission, compared with 14.7 cases in counties with remote learners.

Many proponents of the return to in-person learning and the increase in numbers of positive cases point to the widespread testing that has occurred. Testing did in fact increase 14% in counties with those institutions, compared with 4.2 at remote-learning and non-university communities (-1%). However, the CDC noted that testing rates at the county level in areas without universities were already higher before they reopened.

“If percentage positivity had been stable or declining across the observation period, then efforts on the part of many colleges and universities to conduct or require testing before students’ return to campus and their ongoing surveillance efforts might explain an increase in case counts,” CDC authors said. “However, the concurrent increases in percentage positivity and in incidence suggest that higher levels of transmission occurred in these communities.”

Because of those numbers, the CDC expressed concern that increases in cases at institutions could spread within communities, notably to adults 60 and over. It highlighted a pattern of older adults getting coronavirus some 8.7 days after increases in young adults.

Diving deeper into the results

The study, however, comes with major caveats. Most notably, it does not show the potential impact mitigation strategies implemented by colleges and universities have had, as well as the effects smaller institutions have had on communities at large.

The CDC noted one of the limitations could be the change in format, or “miscalculation”, by some universities from remote to hybrid to in-person. It also said since its focus was on large colleges and universities, the impact on smaller ones on counties could not be determined. The CDC also used population rates from 2019 Census numbers and said the numbers may not include all enrollees.

Nevertheless, the CDC stood by mitigation strategies (social distancing, mask wearing, limiting numbers of guests at live events or having none at all) as “critical” in helping prevent COVID-19 outbreaks. Though many of the recommendations the researchers offered are already being implementing at the university level, the CDC reiterated the importance of keeping those measures in place, including:

  • Testing those who are coming back to school and then continuing those through the end of the spring and in the summer.
  • Increasing that testing and remaining wary of potential spread throughout the community, particularly in locations where students are likely to travel off campus frequently, especially urban areas. Stay apprised of mortality and hospital rates throughout your county.
  • Promoting and enacting policies that further encourage and make mandatory mask wearing and social distancing. Institutions can help by offering daily updates on social media, through targeted email campaigns, website updates and in high-graphic banners on campus.
  • Limiting the number of students, faculty and staff in buildings on campus and especially in dorm locations or in areas where they are known to congregate.
  • Continuing to work with community leaders and public health officials to understand trends off campus that might impact the college or university.