Outbreak of highly contagious norovirus rocks University of Michigan campus

An outbreak of norovirus has caused dozens of students living on the University of Michigan's main campus in Ann Arbor to fall ill with symptoms of the highly contagious disease, the school said.

The Michigan Department of Health and Human Services confirmed the norovirus outbreak after more than 100 students living in university housing complained of vomiting and diarrhea over the last several days, the school said in a statement.

"We believe that this number does not reflect the actual extent of the illness, as students are generally following our advice to self-isolate in their rooms," said Robert Winfield, the university's chief health officer.

Norovirus is the most common cause of food-borne disease outbreaks in the United States. Infections usually occur in places such as hospitals, cruise ships and universities, where people eat and live in close quarters.

During the last several months, outbreaks of norovirus have been reported at a Kansas City dinner theater, a Buffalo Wild Wings Inc restaurant in Kansas and several Chipotle Mexican Grill Inc restaurants in the United States.

Health officials have not determined the cause of the outbreak at the University of Michigan, where a virus-killing cleaning procedure is being used in all dining facilities and residence halls, the school said.

University officials have urged students to wash their hands and to not share food in order to avoid contracting the virus.

About 19 million to 21 million norovirus cases, with 570 to 800 related deaths, are reported in the United States each year, according to the U.S. Centers for Disease Control and Prevention.

(Editing by Frank McGurty and Jonathan Oatis)