The virus arrived with little warning. It would pop up in a dormitory. Then it would beset students living off campus.

As University of Maryland students embark on their winter break, disease trackers have found no obvious ties among the people who fell ill from adenovirus during the fall semester. University officials said 40 students have tested positive, including one who died of an illness associated with the disease.

“There hasn’t been much in the way of commonalities that we’ve been able to detect,” University Health Center director David McBride said. “We’ve looked at where the students who are sick live, what organizations they’re in, whether their roommates are sick. There really is not a consistent pattern coming through.”

Now, they are scouring dorms, offering health warnings and providing online updates.

Adenovirus can cause the common cold, but it can also be the source of serious illness, according to the U.S. Centers for Disease Control and Prevention. The university monitored the outbreak with the state Department of Health and the Prince George’s County Health Department. And as officials have worked to combat the outbreak, specimens have been sent to the CDC for testing. Ten of those specimens have been confirmed as an adenovirus strain that can lead to more significant health problems, a university website says.

“Anytime there are students who are sick on campus, it’s concerning to us and it’s concerning to the kids who get sick,” McBride said. “The students that I’ve seen, some are pretty aware of what’s going on, and some are completely unaware that we’re having something going on on campus. It’s kind of a mixed bag.”

To avoid infection, the CDC recommends handwashing and avoiding contact with those who are sick. Adenovirus-related illnesses are usually treated with rest, fluids and medicine to reduce a fever, the university has said.

“Clinically, this looks like the flu,” McBride said. “People have high fevers, they have [a] cough and sore throat. So in many ways, clinically, it’s not distinguishable from the seasonal influenza that we see every year.”

As the virus spread in College Park, U-Md. officials notified fraternities and sororities so they could take protective measures during social events. They also contacted students with conditions that might put them at higher risk, such as those with asthma or diabetes.

Among the students who have stopped by the student health center for adenovirus testing: Jonathan Allen, student body president. He was feeling poorly, so decided to be tested for the virus. His came back negative.

“It’s better to be safe than sorry,” he said. “Get checked up and take a virus test, if need be.”

During winter break, crews will work to clean residence hall rooms, wiping down bed frames, light switches and doorknobs, McBride said, a precaution that doesn’t normally happen during the gap in the academic calendar.

Earlier in the first semester, U-Md. dealt with concerns regarding mold in a campus residence hall, which became so severe students had to temporarily relocate to hotels.

The student who died of an adenovirus-associated illness, 18-year-old Olivia Paregol, lived in Elkton Hall, the dorm affected by mold, prompting questions about whether the virus and the mold might be related. But the CDC said no link exists between mold and adenovirus, and McBride also dismissed those concerns.

“We’re seeing cases in residence halls across campus, and both on and off campus, and there’s definitely not a consistent connection between students who are living in Elkton and those who we’ve detected to have adenovirus,” McBride said.

McBride said he has spoken with a lot of parents and understands their concerns — one student has died, and others have been admitted to the hospital. So he tries to reassure parents that most healthy people who get adenovirus or another seasonal virus might feel sick but probably won’t suffer complications. He encourages those who fall ill to check in with their doctor.

“There’s nothing unique to our campus that has created this outbreak. It could have easily happened on any college campus,” he said. “I don’t think that people need to be afraid to come back to our campus specifically, as long at they’re following that advice that we’re giving, to keep everyone healthy this season.”

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