Ontario measles case count highest in more than a decade, top doctor urges vaccinations

Vials of measles, mumps and rubella vaccine. Photographer: Justin Sullivan/Getty Images

Cases of measles in Ontario have reached their highest level in more than a decade, the province’s top doctor declared Friday as he urged residents to stay on top of their vaccines.

Dr. Kieran Moore said the province has seen 350 cases, including 31 hospitalizations, of the disease since 2024, when exposure to a travel-related case in New Brunswick led to outbreaks in Ontario and Manitoba.

“It is critical we work together to mitigate further spread of this vaccine-preventable disease,” Moore said in a statement.

In the last two weeks, the province recorded 173 new cases as seven additional public health units in Ontario logged infections. That’s a “sharp increase” over the 78 cases that were reported during the previous two week-period in February, Public Health Ontario (PHO) said in its latest report.

According to the PHO, in 2024 the province saw 64 cases of measles. Between 2013 and 2023 there were 101 confirmed cases.

Most of the current infections are concentrated to southwestern Ontario and Moore said over 96 per cent involve individuals who are not vaccinated or had an unknown immunization status and were exposed in their community or while travelling.

Of the 350 cases in Ontario, 259 were in children and adolescents and 87 were in adults. PHO noted that seven cases were found in pregnant women, five of whom were not vaccinated and two who had previously received both doses of the vaccine. One newborn is also included in the overall case count.

“Vaccination is the most effective way to limit the spread of measles and protect yourself and your loved ones. The measles, mumps and rubella (MMR) vaccine has been in use for more than 50 years and is proven to be one of the safest and most effective vaccines available,” Moore said.

Measles is highly contagious and spread through the air when an infected person coughs or sneezes. It can be transmitted by touching your eyes, nose, or mouth after touching an infected surface.

The symptoms can include fever, cough, runny nose, red watery eyes, and a red blotchy rash.

The recent spread of measles is not limited to Canada. Last month, in Texas, an unvaccinated child died from the disease, marking the first measles death in the U.S. since 2015.

Meanwhile, the World Health Organization and UNICEF said Thursday that cases in Europe doubled in 2024 to levels unseen in more than 25 years, as they highlighted that vaccination rates against the disease have declined since the COVID-19 pandemic.

Moore advised that children should receive two doses of the measles vaccine, their first at 12 months and a second when they are between four to six years old. Children who are fully immunized are considered to be nearly 100 per cent protected from the disease, he said.

Those who are unsure about their immunization status should contact their health-care provider or local public health unit.