Indiana University Campus

LOUISVILLE, Ky. (WDRB) -- Indiana University is seeing its number of mumps cases continue to increase.

According to Fox59, the school says 16 students have now been diagnosed with the illness. This is more than double the seven cases that were reported last week.

The U.S. Centers for Disease Control and Prevention says three or more cases is considered an outbreak. The school also had an outbreak in 2016, when there were 74 confirmed cases of the illness.

According to Indiana law, students are required to show proof of being vaccinated by the end of their first semester, however people can still come down with the illness despite being vaccinated.

School officials say the first two cases of the illness were student roommates living in off-campus housing. Several of the other infected students are members of a fraternity, but authorities have not identified the fraternity.

Indiana is ranked among the top 10 states infected so far this year.

Symptoms of the illness include fever, headache, swollen glands, loss of appetite and muscle aches. Health officials say most people who are infected usually recover in about two weeks.

The school says more students will likely be infected before the semester comes to an end. 

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