The number of students sickened by a contagious gastrointestinal virus at the University of Southern California has grown to about 200.

The university says, however, that Monday's classes are operating normally.

USC students began coming to medical facilities during the weekend with symptoms including vomiting, diarrhea and stomach cramping.

The university says the symptoms last one or two days and in most cases can be managed with rest and fluids.

USC officials advise students who don't feel well or who have had contact with sick students to avoid socializing.

Students, faculty and staff are being urged to frequently wash hands, use hand sanitizers and avoid sharing work stations and food.