The D.C. Department of Health is investigating a possible outbreak of Norovirus at Howard University.

Officials from the school say they reported “a number of cases of gastrointestinal illnesses among our students” to the health department. “Additionally, we have notified our students, faculty and staff to take precautions to prevent contracting this illness.”

Noroviruses are a group of related viruses that cause acute gastroenteritis in humans,according to the Centers for Disease Control. Symptoms include diarrhea, vomiting, and stomach pain. The illness is spread from person to person, through contaminated food or water, and by touching contaminated surfaces.

About 85 similar cases were reported by students at The George Washington University between Feb. 13 and 16.