Canada Poised to Lose Measles Elimination Status as Falling Vaccination Rates Raise Fears of Wider Outbreaks

Canada is about to lose a distinction it has held for nearly three decades. The country has recorded more than 5,000 measles cases across nine provinces and one territory since an outbreak began a year ago in Ontario and New Brunswick, and health experts told Reuters that more cases are likely going undetected.

The rule for keeping elimination status is strict: a country that has an outbreak must get back to zero cases within 12 months. Canada's deadline runs out this week. The United States has until January and Mexico until February. The Pan American Health Organization will meet with member nations in early November, Health Canada said in a statement, and is expected to decide in December. As of October 21, the United States had detected 1,618 cases, in a population about 8.5 times larger than Canada's.

The human cost is already counted. Two premature babies have died of measles this year, one in Ontario and one in Alberta. The virus has hit some religious-minority communities especially hard, including Mennonites, which often have lower vaccination rates.

The numbers behind that spread are plain. In Alberta, about 72% of children had their second dose of the measles-mumps-rubella vaccine by age 7 as of 2024, down from about 82% in 2019, according to provincial data. Ontario's figure fell from 86.1% in 2020 to 70.4% in 2024. Health experts say 95% of a population must be immunized to achieve the herd immunity that protects people who cannot be vaccinated.

The two provinces have had different outbreaks. Alberta has identified almost 2,000 cases since March, the highest per-capita rate in the country. Ontario, with more than triple Alberta's population, reported 2,375 cases as of early October and declared its outbreak over on October 6, after 46 days with no new cases. Ontario-based epidemiologist Nitin Mohan said Ontario moved faster than Alberta on contact tracing and catch-up immunization clinics, so the virus met pockets of immunity that stopped it from spreading. A spokesperson for Alberta's Ministry of Primary and Preventative Health Services said Ontario's outbreak started and peaked earlier, that Alberta is now seeing the same steady decline, and that the government has taken the situation seriously from the outset.

Mark Joffe, who was Alberta's chief medical officer until earlier this year, said more could have been done to raise immunization and limit spread. "If the vaccination rates were high, this would never have happened," he said, allowing that some spread might have occurred but nothing like this. Other vaccines are slipping too. In Alberta, the share of children with four doses of a diphtheria-and-polio-containing shot by age 2 fell from 76.8% in 2019 to 68.9% in 2024. Ontario's polio immunization rate by age 7 dropped from 86.3% in 2019 to 70.2% in 2023. Edmonton infectious disease doctor Lynora Saxinger said other vaccine-preventable diseases would be expected to follow, adding that she sometimes feels the country is heading back to the late 1800s.

There is evidence people can be persuaded. Alberta doubled the number of weekly measles shots given between mid-February and mid-March during a vaccination push, which experts read as a sign that accurate information and easy access work. Joffe said many people do not refuse the vaccine outright; parents of young children simply do not know what measles is, because it did not exist in their lifetimes.

Some Alberta cases have clustered in close-knit Mennonite communities that may not trust or feel connected to public health officials. Tina Meggison, a community health representative with the provincial government, works with Low German-speaking Mennonites in southern Alberta. The oldest girl in a family of 12, she translated for parents who did not speak fluent English. She builds trust in waiting rooms, accompanying people to an appointment and learning their health needs. She said COVID was a negative experience for many, leaving anxiety around vaccine decisions, and that the aim is to equip parents to make informed choices.

The next marker is the PAHO meeting in early November and its expected December decision on Canada's status.