Nine new cases of mumps have been confirmed at Indiana University since last week, bringing the total this semester to 16. It’s likely there will be more before the end of the semester.

“We’re testing around three or four students a day at the health center,” said Chuck Carney, IU spokesman.

Students are required to get two doses of the measles, mumps and rubella or MMR vaccine before arriving on campus. This is the recommended dose for immunity, but it’s not perfect.

Two doses of the MMR vaccine are about 88% protective, on average, against mumps, said Graham McKeen, IU public health manager. By comparison, the same number of doses is about 97% protective against measles.

”That’s why you can see sustained outbreaks in what’s defined as a protected population,” McKeen said.

In addition, there are usually at least a few people on IU’s Bloomington campus each semester who have not received the recommended number of vaccinations. Indiana allows personal religious exemptions that must be signed and submitted in writing. And some people can’t get certain vaccines because of allergies or other medical issues.

This isn’t the first outbreak of mumps at IU or the only outbreak at a U.S. university this year. Temple University in Philadelphia has seen about 140 cases as of last week, according to public radio station WHYY. There were 74 confirmed cases at IU’s Bloomington campus in 2016.

© 2019 HeraldTimesOnline, Bloomington, IN