The number of people sickened by a mysterious outbreak at Humber College has risen to nearly 200 as officials race to figure out its cause, Toronto Public Health said Saturday.

The illness first broke out on Thursday at Humber’s north campus, near Hwy. 427 and Finch Ave. Symptoms so far have included stomach pain, vomiting, cramping, nausea and dizziness.

“This cluster of illness may be due to a food source or is something that is being passed from person to person,” said Dr. Michael Finkelstein, Toronto Public Health spokesperson, via email.

“Once certain viruses are in environments such as student residences, where individuals live close together, preventing the spread of easily transmitted seasonal viruses like norovirus (stomach flu) becomes challenging,” Finkelstein added.

Officials haven’t yet been able to determine what illness they’re dealing with, exactly. However, Finkelstein said figuring that out will help find the source of the outbreak.

Toronto Public Health said an inspection of Humber College Residence found “no significant food safety issues.”

Meanwhile, Humber College says it has doubled cleaning efforts and closed on-campus self serve food facilities, such as salad bars.

“Humber has increased cleaning frequency in the residences and is assisting affected students by delivering water to encourage hydration,” said a statement from the college released late Friday night.

Humber spokesperson Andrew Leopold told the Star that the school is working with Toronto Public Health as they reach out to students to figure out the cause.

“In an instance where a student is feeling ill, they are contacting their resident coordinator or resident staff and then we’re sharing the list of names and information with public health,” Leopold said.