The D.C. Department of Health confirmed more than 20 students at Catholic University have the virus. Catholic University officials said 36 students have fallen ill.
Students have been falling ill since Jan. 21, according to the campus newspaper. The last case was reported Wednesday.
The school believes the outbreak is over because it's been more than 72 hours since the last case was reported, university spokesman Victor Nakas said. The students lived on campus and have been treated.
The university sanitized several buildings and stressed proper hygiene to students.
The virus is the same strand that affected more than 130 students in December 2006. It creates gastrointestinal symptoms, including vomiting and diarrhea.
More than 200 Georgetown University students were sickened by norovirus in October.