MADISON, Wis. (AP) -- A suspected norovirus outbreak at the University of Wisconsin-Madison is growing.

UW officials say 63 students have become sick in Sellery Hall since Nov. 7.

Also, University Health Services has received reports of several dozen sick students in some sorority and fraternity houses and a few suspected cases in off campus housing.

UHS epidemiologist Craig Roberts says norovirus is suspected, but lab tests will say for sure.

The school sent an e-mail to students Friday to provide information in limiting its spread. Students were told how to clean homes where people have been sick and to use extra hand-washing precautions.

Symptoms of vomiting and diarrhea come on quickly and last from 24 to 48 hours.