MINNEAPOLIS (WCCO) – A student at the University of Minnesota has tested positive for measles. It’s the first confirmed measles case in Minnesota this year, and the first measles on campus in at least 20 years.

University health officials say the student came down with the measles after returning home from a trip abroad.

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The University said the 20-year-old man attended classes on the East Bank of campus between Jan. 20 and Jan. 23 before being diagnosed, and went to the University’s recreation and wellness center.

Students received a letter Wednesday alerting them to the situation on the Twin Cities campus.

University health officials say the student is self-isolated at home.

The student reportedly had been vaccinated for the virus, yet still got it. The University of Minnesota does require students to have the MMR vaccine before they can enroll.

Health officials are confident the majority of students have been immunized and therefore won’t be at risk.

However, workers at the Minnesota Department of Health say there is a chance we could see more cases of measles in the Twin Cities.

“We are very concerned about the possibility of additional cases,” Medical Director for Infectious Disease Dr. Aaron DeVries said. “Any time we see a case we are concerned about additional ones occurring. We sent out a message to health care providers to alert them to this.”

The people most at-risk for the highly-contagious virus are those who haven’t been vaccinated and those with weakened immune systems.

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“Even just walking past them. If you are walking by someone who is infectious it can lead to an infection in another person. It’s one of the most infectious diseases we know of,” DeVries said.

Minnesota is one of a small group of states that allows families to opt out of having their children immunized for reasons other than medical. Some of them worry about shots contributing to autism, but doctors dispute that theory.

“There is no evidence that measles, mumps or rubella vaccine causes autism,” DeVries said.

Once the measles vaccine became readily available in the 1960s, the number of cases in the United States dropped dramatically.

As for the measles case at the U of M, health officials say they have identified the classmates and friends of the young man who had the most contact with him. They are watching them closely for symptoms because he was attending class in the days just prior to his diagnosis.

In Minnesota, state law requires students in grades K-12 to show they have received immunizations or an exemption, and colleges are allowed to ask for immunization records as well.

The most recent records show that 91 percent of 2-year-olds in Minnesota have been immunized.

If you are an adult and don’t know if you’ve been vaccinated for measles, you can still safely get immunized. Just talk with your doctor.

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Measles bring on a rash, fever and a bad cough, so see your doctor immediately if you observe these symptoms.