Toronto Public Health has confirmed 21 new mumps cases in the city, bringing the total number of cases to 64.

Five cases are among staff or students at four different public schools, wrote Toronto’s associate medical officer of health, Vinita Dubey, in an email to Metro.

Four cases are confirmed at Ryerson University.

“While the cases previously had a link to west downtown bars, there is now broader community spread,” Dubey added.

The outbreak is “more than the city has seen in the past 20 years,” she wrote, and given that the incubation period is two to three weeks, officials won’t know until then whether the new people with mumps have infected others.

Not even two weeks ago the total stood at 43 cases.

Dubey recommends people check their vaccination records, as the Measles Mumps Rubella (MMR) vaccine is “still the best protection against mumps.”

People aged 24 to 47 and those born outside of Canada probably have not received the recommended two doses of the vaccine and should visit their doctor to get it, she added.

There’s no treatment for the viral disease. Symptoms include fever, headache, and swelling in the cheeks, jaw or testicles. Complications can include encephalitis (brain infection) or meningitis.

Given the number of cases at Ryerson, on Tuesday Toronto Public health instructed officials at the downtown university to send a bulletin to students and staff urging them not to share drinks or utensils, get vaccinated, and stay home if sick.

Director of student health and wellness Allan Macdonald wrote in an email that he cannot discuss details due to privacy concerns, but said they are reviewing mumps screening protocol with Student Health and Wellness administrative staff.

Students and staff can get a booster shot for free, if necessary, from the Ryerson Medical Centre, he added.