As many as 200 people may have been sickened with norovirus at the Harvard Faculty Club in Cambridge, MA, the Boston Globe reported Thursday. So far there have been no hospitalizations.

Harvard Faculty Club, an upscale restaurant and lodge, voluntarily closed the club last week when patrons began reporting illnesses. The club brought in an outside cleaning crew to disinfect the building, and after receiving approval from the city reopened on Sunday, April 4. About 100 full and part-time employees were also screened for norovirus.

Between that Sunday and the following Tuesday morning, however, about 100 people reported symptoms consistent with norovirus, including nausea, vomiting, diarrhea, and some stomach cramping, forcing the club to close for a second time.

According to Louise Rice, director of public nursing for the city of Cambridge, the club will remain closed for at least seven days while the building is cleaned again.

Cleaning crews will need to scrub every appliance and surface of the building, from doorknobs to pencils and pens.

“It’s very hard to rub out entirely,” Rice said.

When asked where the virus came from, Rice said it is possible that at least one employee was carrying norovirus without any noticeable symptoms, despite the screenings. Otherwise, she said, it came from somewhere in the outside environment.

After public health officials confirmed the presence of norovirus, Crista Martin, a spokesman for Harvard’s hospitality and dining services, said the Faculty Club will follow all of the recommendations made by the City.

“We will work with them to eliminate this concern and safeguard the health of our customers,” she said.

The Harvard Faculty Club is asking those who became ill after dining there to contact the Cambridge Department of Public Health at 617-665-3800.