Eight patients are currently under observation in the Lanaudière for signs of the infection.
In other parts of North America, measles is making a comeback, at least in part due to parents not vaccinating their children.
In 2011, Quebec was hit with the biggest outbreak of measles in North America, recording nearly 700 cases. At that time, doctors said many of those cases were people who had not received the measles, mumps and rubella vaccine.
A major vaccination program was launched during the epidemic, but doctors say there are still parents who choose not to vaccinate their children.
Health officials believe two to three per cent of children in Quebec are not vaccinated.
Quebec parents confused about vaccination
Dr. Marie-Astrid Lefebvre, a pediatric infectious disease specialist, said parents ask her whether or not vaccination is a good idea more often than she’d like.
She said many of the concerns against vaccination are linked to a fraudulent study in a 1990s medical journal that linked the vaccine to autism.
"Unfortunately, I don’t think there is enough publicity stating that this claim was completely false,” she said.
"I still have parents these days talking about the autism links. So I have to explain it all over again, every time.”
Health officials cannot force people to vaccinate their child - parents have the option of signing an exemption form.
However, measles is extremely contagious. Ninety per cent of people who are exposed to the virus who are not immune will catch it.
Common symptoms include a rash, fever and a cough. In rare cases, it can lead to permanent brain damage or seizures. Those complications increase in vulnerable populations.
Lefebvre said the people who are the most at risk are people with a weakened immune system.
"So children who get chemotherapy, or children who have HIV, of infants less than a year who can not yet get vaccinated…. those people are at higher risk of complications,” she said.
Quebec’s health minister, Gaétan Barrette, added his voice to the chorus of health care professionals imploring parents to vaccinate their children.
"Immunization, vaccination is the absolute weapon. It works,” he said.
In case of an outbreak in Montreal, parents could be asked to keep their child home until the outbreak passes.
Vaccination rates in Quebec