Seven cases of mumps among University of Minnesota students have been confirmed since Thursday.

State health officials announced six cases of mumps on the University of Minnesota’s Twin Cities campus Thursday, Medical School Dean Dr. Brooks Jackson said in a campus-wide email Thursday.

On Sunday, University spokesman Steve Henneberry said another case of mumps has been confirmed. He said two of the affected students got the infection from travelling, which could be the source of the outbreak.

All six cases of the highly contagious viral infection reported Thursday were mild and involved students, according to the email.

Mumps is transmitted through saliva or mucus from the mouth or nose and is distinguished by a swollen jaw and cheeks. It can spread through coughing, sneezing, sharing eating utensils and cups and touching surfaces with unwashed hands, Jackson said in the email.

Symptoms include fever, tiredness, headaches, swollen and tender salivary glands under the ears, muscle aches and loss of appetite, according to the Centers for Disease Control and Prevention.

University students, faculty and staff who have been immunized against mumps have a low risk of being infected. In addition, the University population has a high immunization percentage because of enrollment immunization requirements, Jackson said.

He advised those with symptoms to stay home, isolate themselves and make an appointment with Boynton Health.

Mumps was common in the U.S. until vaccinations became routine, according to the Mayo Clinic.

Complications of mumps include deafness, encephalitis and meningitis, according to the CDC.