The Return of Measles: A Public Health Crisis in Canada
In a shocking turn of events, measles, a disease once thought eliminated, has made a comeback in Canada, raising serious concerns and questions. This resurgence highlights a critical issue that demands our attention.
Back in 1998, Canada proudly declared measles eliminated, only to see it resurface over two decades later. The numbers are staggering: a whopping 1,912 cases in the US in 2025, compared to a mere 59 in 2023. And just north of the border, Canada is facing its own battle with measles, reporting nearly three times as many cases despite its smaller population.
So, how did this happen? And what can be done to regain control?
Measles, a highly contagious virus, infected tens of thousands annually in Canada before the measles vaccine was introduced in 1963. The disease was nearly universal, with studies showing an astonishing 97% to 99% seropositivity in specific cohorts, indicating widespread infection. This, combined with the deadly nature of the disease, made it a formidable public health challenge.
Through a combination of the vaccine and a dedicated public health campaign, Canada achieved elimination status in 1998. But it's important to note that elimination doesn't mean eradication; it simply means the disease is no longer actively spreading within a region. True eradication, like with smallpox and rinderpest, is a much rarer feat.
The risk with elimination is that if public health efforts lapse, the disease can return. And that's exactly what happened in Canada. A 2011 outbreak primarily in Quebec threatened Canada's elimination status, and now, the current outbreak is concentrated in Alberta and Ontario.
The outbreak in Ontario started with an individual contracting measles at a Mennonite gathering in New Brunswick. The virus then spread through low German-speaking communities in Southwestern Ontario, where vaccination rates have historically been low. In fact, almost all those infected in Ontario were unvaccinated.
The situation in Alberta is similarly concerning. Despite only comprising 12% of the population, Alberta accounted for a staggering 37% of Canada's measles cases in 2025. This is largely attributed to the large Mennonite population in the province, with vaccination rates as low as 56% for two doses of the MMR vaccine in some areas.
However, the drop in vaccination rates isn't solely due to these communities. Since the COVID-19 pandemic, vaccine hesitancy has risen, leading to increased mistrust in the healthcare system and the spread of misinformation. This is evident in major cities like Calgary and Edmonton, where vaccination rates are in the high 70s or barely reach 80% even in the most vaccinated districts.
As a result, Canada has officially lost its measles-free status, as recognized by the Pan American Health Organization. This is more than just an embarrassment for Canada's health system; it puts vulnerable Canadians, especially those who are immunocompromised or too young to be vaccinated, at serious risk. The potential for intercommunity spread through hospitalized children is a real concern.
While the brunt of the outbreak appears to be over, with no reported cases in Alberta since December 13, 2025, and in Ontario since December 6, 2025, new cases are still being reported in Manitoba and Quebec. Regaining elimination status may take time, as seen with Brazil and Venezuela, who only regained their status in 2024 after losing it in 2018 and 2019, respectively.
The road to eliminating measles from Canada once again may be long, but public health experts believe it's achievable. With increased investment in Canada's public health system and efforts to rebuild confidence in vaccinations, Canada has the tools to tackle this crisis and regain its measles-free status.
