More than a dozen students at Florida State University (FSU) are sick with hand, foot and mouth disease, an illness that's usually seen in young children. So why are college-age adults contracting the disease?

The viral illness can cause fever, painful mouth sores, and a skin rash on the hands and feet, according to the Centers for Disease Control and Prevention (CDC). It usually affects kids younger than 5 years old.

But it's not surprising to see cases of the disease on a college campus, as it can sometimes affect adults, said Dr. Amesh Adalja, an infectious-disease specialist and a senior associate at the University of Pittsburgh Medical Center's Center for Health Security.

"Some people might escape infection as a child, and they get it at a later age," Adalja said. 

In addition, a number of viruses that belong to a group called enteroviruses can cause the illness. So it's possible that some people who were infected as children have immunity to just one type of the virus, but not another type, leaving them susceptible to a second infection, Adalja said.

What's more, the virus is highly contagious, and the close-quarters of a college dorm can magnify the outbreak, meaning there will be more cases than there would be in other settings, Adalja said.

"People are definitely exposed to each other at a higher intensity" in college dorms, where they share close living spaces, Adalja said.

If the virus arrives on a large college campus, it might be only a matter of time before more people are infected. "This class of viruses is highly contagious, and if it finds the right person, it's going to cause [illness]," Adalja said.

Workers at FSU are now sanitizing the dorms of the affected students, as well as public spaces on campus, according to a university statement. But officials also advised all students living in the school's housing, or fraternity and sorority houses to "sanitize their residences thoroughly and install bottles of hand sanitizer in each residence," the statement said.

There is no specific treatment for the disease, but people who are sick usually get better in a few days, FSU said.

To prevent the spread of the disease, the CDC recommends washing hands often, cleaning frequently touched surfaces, and avoiding close contact with people who have hand, foot and mouth disease.

Original article on Live Science.

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