University of Illinois officials have blamed an unpredicted surge in Covid-19 cases to some students partying and avoiding quarantining and contact tracing efforts.
The university reported 1,754 new cases from Aug. 15 when students started coming back to campus, through Sept. 8, although a team of researchers working directly for the university administration had projected only 500 to 700 cases by Thanksgiving.
As a result, the university has called for undergraduate students to stay in their rooms and apartments until Sept. 16 except for going to classes, getting food and other limited activities.
“Over these past few days, the irresponsible actions of a small number of students have created the very real possibility of ending an in-person semester for all of us,” wrote Chancellor Robert J. Jones in a Sept. 2 mass email. “Their poor choices have led to a concerning and rapid increase in the number of new undergraduate COVID-19 positive cases.”
But last month, two independent university researchers warned that the number of Covid-19 cases could soar if the cities of Champaign and Urbana did not return to previous restrictions that included closing operations of bars and restaurants except for deliveries.
The researchers, Eric Jakobsson and Santiago Núñez-Corrales, said their computer model projected an additional 800 cases if the community did not take measures that included closing indoor operations of bars and restaurants. In total, they said cases could peak between 1,300 and 2,800 cases in the first few weeks of the University of Illinois semester, depending on the mitigation efforts the campus and cities chose to employ.
The cities responded partially by closing indoor operations of bars in the Campustown area by the university and tightening social distancing policies for other bars and restaurants.
The campus had already instituted a series of health measures, including twice-a-week testing of students, faculty and staff; wearing masks; arranging for quarantine facilities; and designing a phone app that would alert people if someone who had tested positive was nearby.
Champaign County as a whole, has 3,728 total cases, as reported from early March to Sept. 9 by the Illinois Department of Health.
The university has run 256,077 tests since beginning testing in July and is currently at a past seven-day case positivity rate of 0.90%.
As of September 11, 25 students are quarantining in University Housing, and 103 are isolating in Housing, according to Associate Chancellor for Public Affairs Robin Kaler. 276 quarantine and isolation spaces are currently empty.
Kaler later said the Illini Union Hotel was helping with housing and quarantining and that they wanted to give students in quarantine isolation and privacy.
The university’s team of researchers, led by Nigel Goldenfeld and Sergei Maslov, modeled expected case numbers under a variety of mitigation efforts. They expected that the greatest amount of mitigation efforts would result in 686 cases by Thanksgiving.
The estimate includes an initial “bump” of around 200 imported cases from returning students, but the bump turned out to be more than 1,700 cases. Mitigation efforts modeled to produce this result include twice-weekly testing, mask, online classes, and manual contact tracing. Most classes at the university are online, but there are some in-person classes or hybrid classes of online and in-person instruction.
According to Meghan Hazen, the registrar at the university, “About 58% of all students are taking only online courses this semester.”
UIUC mitigation efforts align on each aspect except for being completely online. Efforts currently required by the university include twice-weekly (2TW) testing for undergrads, once-weekly testing for grad students and faculty, masks, and usage of the “Safer Illinois” app which is used for contact tracing and building access.
Researchers Jakobsson and Núñez-Corrales were closer to the mark with their predictions. Jakobsson stated that Sept. 1 is “within a day or two of when we projected the peak would be.”
They said the twice weekly testing is responsible for having a lower positivity rate (currently 1.05%) than they predicted (2%).
“We realized that our projections undervalued the University’s testing….The great advantage of testing twice in short succession is that (it) reduces the fraction of false negatives,” Jakobsson wrote in an email.
Núñez-Corrales also wrote via email to say, “When compensated by multiple testing rounds of testing, one can expect in our model the peak to lower down to 1300 at the peak under Phase 3 conditions.
The university has been in the less restrictive Phase 4 of reopening and only recently (Sept. 2) moved back toward restrictions under Phase 3. Champaign county is still in Phase 4.
Jakobsson and Núñez-Corrales emphasized the difference in their positivity calculation and the other researchers’ calculation. Jakobsson said the percentage formula they implemented used the total infected/total population. He said that was different from other researchers’ calculation, which was positive tests divided by/total tests. That is, total population does not equal the number of people tested until every member of the community is tested.
To slow the spread of the virus, Jakobsson wrote, “the entire containment totally depends on asymptomatic infected people accepting confinement until their infection has run its course. I totally support coming down as hard as possible on anybody who has tested positive and evaded isolation.”