First 2 weeks critical to stem college COVID-19 outbreaks

Stanford University researchers say superspreader events that extend beyond campus can occur, though institutions did well to mitigate them in the fall.
By: | January 13, 2021
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New data released Wednesday by Stanford University scientists and the Taylor & Francis Group shows the potential for COVID-19 superspreader events to occur within two weeks at colleges and universities that reopen and don’t take strict measures when cases occur.

Using results from the fall 2020, researchers noted how prevention measures, such as a return to online learning and tracing strategies, can affect campuses and much-less-prepared counties where institutions are located.

The research, published in the peer-reviewed Computer Methods in Biomechanics and Biomedical Engineering, looked at the impact the virus had on 30 colleges and universities that chose to either open in-person, online or in hybrid models in the fall.

Computer models developed by the university showed that 14 of the 30 had outbreaks that directly impacted communities surrounding their campuses. Interestingly, six of those were in online-only instruction while six were in hybrid. Two were in-person only.

“Strikingly, these local campus outbreaks rapidly spread across the entire county and triggered a peak in new infections in neighboring communities in more than half of the cases,” said senior author Ellen Kuhl, Stanford’s Chair of Mechanical Engineering and the Chair of the U.S. National Committee on Biomechanics. “It is becoming increasingly clear that these initial college outbreaks are independent local events driven by campus reopening and inviting students back to campus. Our results confirm the widespread fear in early fall that colleges could become the new hot spots of COVID-19 transmission.”

How well institutions handle reopening, or don’t, could have dire consequences. Stanford researchers say the potential incidence of 1,000 cases per 100,000 people per week is not out of the question in college communities, far surpassing the peak of second of first waves, which were around 75 to 100. They say some colleges experienced 1 in 5 students testing positive last fall.

Hannah Lu, lead author on the study, noted the disparity of cases that occurred on college campuses compared with local numbers.

“Policymakers often use an incidence of 50 COVID-19 cases per 100,000 people per week as a threshold for high-risk counties, states, or countries,” she said. “All 30 institutions in our study exceeded this value. The number of students who had become infected just throughout the fall is more than twice the national average.”

And yet, colleges and universities managed to get through the semester. In fact, after making significant changes – making students accountable for their actions, reinforcing COVID dashboards and beginning widespread testing of students – institutions were able to hold the line against further spread.

“College administrators should be applauded for their rapid responses to successfully manage local outbreaks,’ Kuhl said. “All reported campuses pursued regular surveillance testing, weekly or even twice per week, combined with aggressive test-trace-isolate strategies.”

How colleges reacted

The authors say August 2020 should be kept front of mind as colleges and universities reopen this semester. Many that started back up in the fall struggled to get a grip on COVID-19 after opening.

Lu mentioned Notre Dame as an example of an institution that appeared to have a solid plan only to get hit hard by cases.

“All 12,607 students were tested before the beginning of class and only nine had tested positive,” she said. After only a couple of weeks, numbers skyrocketed. By the end of the semester, it had 1,831 cases. The rate of infection was 14.5, nearly double that of its county (7.8%). Compare that to a university of the same size and in relative proximity – Carnegie-Mellon University in Pittsburgh, which offered a huge number of remote courses to all students as well as some in-person, and reported only 141 cases.

Another institution that struggled early on was the University of Wisconsin-Madison, which contended with both spread on campus and throughout the state. UW had 5,812 positive cases in the fall, according to Stanford’s researchers. An institution of the same size, the University of California at Los Angeles, opened only for 8% of students and had 712 cases.

The University of North Carolina started in person and experienced 177 positive cases in the first week before moving its classes online. The move made a huge difference, as it reported a 5% positivity rate before the end of the semester.

For the study, Stanford researchers culled data from 30 dashboards for colleges that updated their dashboards daily. The two universities with the most number of cases in the study were the University of Florida (5,630) and Clemson University (5,431).

After a really rocky start in which Clemson twice reported 172 cases on separate days in August and March, it slowed its numbers through November. In the first week of January, its positive numbers ranged from 41-63.

According to UF’s dashboard, it posted four straight days of 100 or more cases in early September. On the day classes began, it noted 46 positive tests. By Sept. 7, that number jumped to 174. Not only were student numbers high, but more than 1,100 employees tested positive. The University of Washington, a school with largely the same enrollment, had 958 cases.

And yet, Clemson and Florida along with many other institutions that posted a spike in incidences – University of Illinois (4,407), Purdue (3,611), Kentucky (3,107), University of Arizona (2,959) and Brigham Young (3,665) – managed to finish out the semester.

“The majority of colleges and universities were able to suppress campus-wide infections. As a result, for most institutions, the outbreak dynamics remained manageable throughout the fall, with narrow spikes of less than 300 cases per day,” Lu said, noting that the campus death rate remained very low at 0.02%. But she added, “the neighboring communities were less successful in controlling the spread of the virus.”

Moving forward

Several large institutions fared well in their overall response, reporting less than 1,000 incidences this fall, including institutions from a mix of location that have more than 10,000 students – Cornell University (308), Emory University (392), Boston University (600) and Vanderbilt (816).

Why did they fare so well?

Authors credit “tight outbreak management” and a quick pivot to fully remote learning when outbreaks occurred. They said that can mitigate spikes in close to 14 days.

“Our study suggests that tight test-trace-isolate strategies, flexible transition to online instruction, and–most importantly–compliance with local regulations will be critical to ensure a safe campus reopening after the winter break,” Kuhl said.

Even many of the colleges and universities they studied that did experience a quick jump in cases, performed regular testing as well as strong quarantine and isolation measures. That likely kept cases lower than they could have been.

It is worth noting, Kuhl said, that all of the strategies employed by institutions won’t matter if students, faculty and staff don’t follow public health and campuswide guidelines and recommendations.

For colleges and universities, it is vital that they continue to remain steadfast in posting numbers and updating their dashboards. Their outreach to the campus community is also imperative, both providing updates and also ways in which individuals can remain safe and be tested. Colleges should be developing and rolling out vaccine plans before  vaccine become available and should also consider creating vaccination dashboards.