The migration of students back to college campuses this fall has led thousands of young people to contract Covid-19 who probably would not have otherwise gotten the disease.
But have those cases led to outbreaks beyond their campuses?
A report published on Wednesday by the Centers for Disease Control and Prevention suggests that it is a possibility. Cases among younger people surged in June, July, and August, the report says, and younger people probably spread the disease to older populations.
The CDC said the data “provides preliminary evidence that younger adults contributed to community transmission of Covid-19 to older adults.”
Public-health officials say they have not yet seen evidence of the surge in community spread that they feared.
But in conversations with The Chronicle this week, public-health officials in counties and states that saw outbreaks on college and university campuses this summer said that if they had seen evidence of infection in the areas surrounding those campuses, it was limited.
Take Washington State University, for example. It did not hold classes in person this semester, instead opting for remote instruction, but about 12,000 students returned to the Pullman area anyway, according to Troy D. Henderson, director of the local county’s public-health department.
The county saw a huge surge in cases at the end of the summer. On August 20 the county had seen a total of 142 cases since the start of the pandemic, according to the state’s dashboard. But from August 21 to September 23, that number jumped to almost 1,200 cases.
Henderson said that about 95 percent of the new cases were people ages 18 to 25, suggesting it’s the students who are contracting the virus.
There has been only a small amount of spillover from younger people to the older population in the community, he said. One person over the age of 65 was hospitalized during the recent surge, he said; so far there have been no fatalities.
“We’re hoping it stays that way,” Henderson said.
What They Feared
At the University of North Carolina in Chapel Hill a surge in cases prompted the campus to reverse course and go remote after first opening in person. By Friday a total of 1,208 students and employees had been infected, according to the university’s dashboard.
Todd McGee, the community-relations director for the local county’s health department, said that there was a lot of concern in the region that the university’s decision to reopen would cause outbreaks in Chapel Hill and beyond. Orange County’s health director had even recommended to the university in a letter that classes be held remotely for the first five weeks of the semester, The Daily Tar Heel reported.
That didn’t happen, but McGee said Orange County hadn’t seen the kind of community spread he and other officials had feared.
“A few weeks after students returned, we started noticing a dramatic increase” in cases for 18-to-24-year-olds, he said. “We can’t say we’ve detected that it’s resulted in a large number of cases in all the age groups.”
John Silvernail, the health director in Pitt County, home of East Carolina University, said the same thing.
“Surprisingly, I think the spread into the general population or non-ECU population was quite limited,” he wrote in an email to The Chronicle. “I would attribute this to quick action by ECU Student Health Services and Pitt County Health Department to control the outbreak.”
And in Johnson County, Iowa, where the University of Iowa is located, the manager of the community health division, Samuel Jarvis, said a spike in the number of coronavirus causes seemed to be confined to the university.
“We had an extremely large surge in the beginning of August,” Jarvis said. “It was expected. But when it happens, it’s somewhat alarming and concerning.”
Johnson County’s disease-investigations team meets daily to talk about trends and look carefully at the data, he said. So far, its members haven’t detected a big surge in cases among people in their 30s, 40s, 50s, and beyond.
“We didn’t necessarily see the spillover we were concerned about,” Jarvis said.
Detecting the Spillover
Most of the health officials said they were surprised by the limited spillover into the community. They attributed it to measures the universities had taken to quarantine students and, in some cases, move to remote learning. Henderson, the health director in Washington State’s county, said it hadn’t expected that many students to return, so at first, it lacked enough testing. Once the county ramped up testing capacity, he said, it was able to contain the virus better.
Yonatan Grad, an assistant professor of immunology and infectious disease at Harvard University, said a college’s ability to contain the virus depended on its mitigation efforts and the efforts of the community in which it is located. If everyone is wearing masks and staying distant, it’s possible that outbreaks can be contained.
It also depends on the campus’s connectedness to its surrounding area.
“If the college students are in dormitories and those are all separated from the communities in which they reside,” he said, “and there really aren’t that many opportunities for those individuals to interact with their neighbors, that lowers the likelihood of spread or slows the appearance of those cases in the communities.”
He cited the NBA’s “bubble” — a closed-off zone in Walt Disney World for players, coaches, and a limited number of guests that the league created to keep teams in the playoffs isolated from the coronavirus — as an example of how an institution was protecting its population from outbreaks. Even as case numbers have grown in Orlando, Fla., and the surrounding area, Grad said, the NBA has been able to keep the so-called bubble largely untouched.
But colleges and universities can’t really create bubbles, so it’s too early to call this approach a success. Plus, even a small amount of transmission to the older population can be deadly.
Christopher R. Marsicano, an assistant professor of the practice of higher education at Davidson College and an author of a study this week that found that colleges that had opened probably contributed more than 3,000 coronavirus cases per day in their counties, said it could be a couple of weeks before those counties detected spillover into the surrounding community.
“It would be shocking, given the numbers we found, if it was exclusively students,” he said. “There are more cases per day than institutions are reporting per day. That would suggest there is at least some spillover.”
