An outbreak of hand, foot and mouth disease has been reported at Princeton University, affecting 13 students, according to a story on NJ.com.

The campus of Princeton University
(Princeton University, Office of Communication)

The cases were initially reported on Thursday, the website said.

According to the Centers for Disease Control, HFMD "is a common viral illness that usually affects infants and children younger than 5 years old." The disease can also occur on adults and often begins with a fever, sore throat reduced apetite and a general feeling of malaise. The illness can cause painful sores to develop in the mouth as small, red spots that blister and could become ulcers. Later symptoms may include a skin rash with red spots on the palms and soles of the feet. The sores may also appear on other parts of the body.

"Not everyone will get all of these symptoms. Some people, especially adults, may show no symptoms at all, but they can still pass the virus to others," the CDC website states.

In very severe, and rare, cases, HFMD can cause meningitis, encephalitis, fingernail and toenail loss, but those are uncommon, according to the CDC. There is no actual treatment for the disease, other than over-the-counter pain medicines and mouthwash. To prevent the spead of the disease, the CDC recommends taking steps similar to preventing cold and flu: frequent hand-washing as well as cleaning and disinfecting surfaces.

According to NJ.com, officials at the university are unsure what caused the Princeton outbreak.