Parents, educators on alert as Ontario measles outbreak rises to 572 cases

A vial of the measles, mumps and rubella vaccine is shown at the Lubbock Health Department in Lubbock, Texas on Feb. 26, 2025. (Mary Conlon / AP Photo)

TORONTO -- A mother of an infant, a principle of a religious school, and a public health physician -- they all share the desire to get kids vaccinated as the province records another 102 new cases over the past week.

Public Health Ontario says there have been 572 cases since the outbreak began in October, 453 of them confirmed and 119 probable. Of the 42 people requiring hospitalization, two have required intensive care, and 36 have been children -- most of them unvaccinated.

The highly infectious disease is still predominantly impacting unvaccinated infants, kids and teenagers, most in Southwestern and Grand Erie public health units.

Rosemary Tamburini’s nine-month-old baby is just a few months shy of his first measles shot.

But she doesn’t want to wait to vaccinate her child any longer, and is considering early immunization.

“I don’t think I’m alone in that. I’ve had discussions with several moms in Ontario who are in a similar situation looking to potentially get vaccinated early,” Tamburini, who lives in Etobicoke, said.

The measles vaccine typically starts for babies at one-year-old, but Ontario public health units have made the first shot available to babies as young as six months in response to the outbreak.

Geographically, measles has spread to Waterloo and Lambton. In Chatham-Kent, cases have nearly doubled to 39 in the past week, and the spread continues in Huron Perth where 55 people have been sickened.

Almost all of the cases are tied to a multi--jurisdictional outbreak that began with a travel-related case in New Brunswick that spread to Ontario and Manitoba. Ontario’s medical officer of health sent a memo to colleagues in local public health units earlier this month stating the origin of the outbreak was at a large gathering with guests from Mennonite communities in New Brunswick last fall.

Dr. Kieran Moore said cases are “disproportionately affecting some Mennonite, Amish, and other Anabaptist communities due to a combination of under-immunization and exposure to measles in certain areas.”

Not long after Christmas, a student at Walsingham Christian School, a private school in Norfolk County, part of the Old Colony Mennonite church, got measles.

Principle Martin Klassen said they called an impromptu meeting with parents at the school to discuss vaccination, also distributing information in Low German for a few parents who aren’t fluent in English. Most kids at the school are vaccinated, Klassen said. And for parents whose kids were not, “They were open to it,” he said.

In total four kids tested positive for measles at the school around late January and early February, and all are back to school.

“Families deciding to get their children vaccinated or deciding to not get their children vaccinated has actually nothing to do with the baptism view that we have of religion. Absolutely nothing. Our ministers, our church, our brotherhood, we wouldn’t be spreading a view on should you or should you not get vaccinated,” Klassen said.

Further northeast in the province, Kelly Moorcroft teaches music at schools in Ottawa. Her first reaction to the outbreak in Ontario was anger and frustration.

“When I see something like measles making a comeback when it had been declared eradicated, it’s so discouraging,” Moorcroft said.

So far, Ottawa has not reported measles cases, but she’s watching closely, and preparing.

“If I were to have a student come into my studio and flat out say, ‘I’m not getting vaccinated,’ I’m not sure what I would do with that student. I would probably fire them from my studio,” she said.

But Moorcroft also acknowledged that many people in Ontario don’t have a family doctor to keep them on schedule with vaccinations.

“I’m lucky I have a doctor. There’s a lot of people out there that don’t have those.”

Outbreaks are also being monitored in other provinces, though the case counts are smaller -- including in British Columbia, Manitoba and Alberta where 18 people are diagnosed, most of them minors. Last week, Saskatchewan confirmed its second case and said it was investigating a third. The latest numbers in Quebec are unchanged at 40 cases since last week.

Measles is one of the most contagious diseases in the world. The World Health Organization says the virus can remain active in the air or on infected surfaces for up to two hours.

It usually begins with a fever, cough, runny nose and red watery eyes, followed by a red blotchy rash that starts on the face and spreads to the body and limbs. The virus can lead to pneumonia, inflammation of the brain and death.

The number of cases reported in Ontario over the last week is more than the number of cases recorded over the course of a decade between 2013 and 2023.

This report by The Canadian Press was first published March 26, 2025.

In the United States, this year there have been 378 confirmed cases recorded across 18 jurisdictions, according to Centers for Disease Control and Prevention (CDC) data from last week.

Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.

Hannah Alberga, The Canadian Press