Ontario is seeing a renewed surge in measles cases, with 155 new infections reported over the past week, bringing the total number of confirmed cases in the province to 816 since the outbreak began last fall.
After several weeks of holding steady at around 100 cases per week, the sudden increase has dampened earlier optimism from public health officials, who had cautiously hoped the outbreak was beginning to stabilize.
Public Health Ontario reports that 61 people have now been hospitalized due to measles, including 47 children—an increase of 11 hospitalizations since last week. Officials continue to stress that unimmunized children remain the most vulnerable and most affected group in this outbreak.
The majority of cases remain concentrated in the province’s southwestern public health region, but the virus has now spread to two additional public health units: Hamilton and Northeastern Ontario, which includes Timmins and Englehart.
Dr. Ninh Tran of Southwestern Public Health noted that vaccination rates in the region have spiked in response to the outbreak. From January to April, there’s been a 130 per cent increase in measles vaccinations compared to the same period last year, with nearly 1,000 more doses administered.
In schools, officials have begun suspending students who are not fully vaccinated, as part of a broader push to boost immunization coverage. The outbreak has also renewed urgent calls for Ontario to digitize its vaccine record system—a recommendation public health experts have been making for over a decade.
Currently, Ontario still relies on outdated yellow paper immunization cards, which are easily lost or overlooked. “People can’t seem to find them,” said Dr. Tran. “They have to contact their health-care provider and then report it to us.” He emphasized that an electronic vaccine registry is “absolutely critical” for tracking coverage and responding to outbreaks more effectively.
Elsewhere in Canada, measles cases are also climbing. Alberta’s case count nearly doubled over the past week to 46, while Saskatchewan now reports six infections. Quebec has remained steady at 40 cases for a fourth straight week. Manitoba, meanwhile, has recorded 10 cases since February, including one involving a flight passenger traveling from Toronto to Winnipeg.
Measles typically begins with flu-like symptoms—fever, cough, runny nose, and red watery eyes—before progressing to a red blotchy rash that spreads from the face to the rest of the body. In some cases, the virus can lead to serious complications, including pneumonia, brain inflammation, and even death.
Health officials continue to urge parents to ensure their children’s vaccinations are up to date and to consult their health providers if immunization records are missing or incomplete.