measles in canada: latest case stats, impact and resources

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canada is facing the largest outbreak of measles since the disease was eradicated in 1998.

by karen hawthorne

published may 23, 2025

5 minute read

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5 minute read

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the highly contagious disease continues to spread primarily among unvaccinated children, infants and teenagers, both in ontario and alberta where case numbers are causing most concern. getty images

statistics will change as new measles cases are reported and we will endeavour to keep this article updated with information provided by the government of canada. this article was last updated on may 23, 2025.

canada is facing the largest outbreak of measles since the disease was eradicated in 1998. the highly infectious disease has people across the country concerned for the safety of vulnerable populations like children, pregnant women and those with compromised immunity. as well, anyone who is not vaccinated against measles is at risk.

why is it such a threat? while measles can be a rash and fever that resolves over a few days for some, the consequences can be much more serious, especially for children under age five. common complications are diarrhea and ear infections, but the disease can lead to hearing loss, pneumonia, swelling or infection of the brain, and death.

because measles is an airborne disease that spreads so easily through respiratory droplets, when an infected person is even just breathing, virus particles are released into the air. the particles can remain infectious for up to two hours, even after the person has left the area. also, an infection can spread four days before someone has the characteristic red rash until four days after its onset, so people transmit the disease without knowing they’re infected.

note the risk assessment information from the public health agency of canada for transmission of measles through 2025:

“the likelihood of prolonged transmission in the next six months is moderate-high, driven by the outbreak involving communities with low immunity to measles. the most likely spread scenario is one where transmission will continue within socially connected communities with low immunity to measles, as social events and mobility among and between these communities will facilitate introductions across multiple provinces and territories. although periodic introductions into populations with higher levels of immunity to measles in canada are expected to result in limited chains of transmission, exposure events in higher-risk settings, such as healthcare facilities or schools, are of concern.”

measles stats in canada on the rise

canada has recorded 1,593 confirmed and 253 probable measles cases this year for a total of 1,846, according to the federal government’s latest monitoring report. the vast majority of these cases are in ontario.

here’s the current breakdown of total 2025 cases:

ontario – 1,460
alberta – 287
saskatchewan – 27
manitoba – 24
british columbia – 8
northwest territories – 1
nova scotia – 1
prince edward island – 2
quebec – 36
new brunswick – 0
newfoundland and labrador – 0
nunavut – 0
yukon – 0

the outbreak began in new brunswick at a mennonite community gathering in october 2024 and continued to spread in ontario with related cases that followed as reported in alberta, british columbia, manitoba, northwest territories, prince edward island, quebec, and saskatchewan.

the highly contagious disease continues to spread primarily among unvaccinated children, infants and teenagers, both in ontario and alberta where case numbers are causing most concern. so far in ontario, public health ontario’s measles report says there have been 129 hospitalizations, including 10 people in intensive care. the report adds that 95 per cent of those hospitalized were unvaccinated, including 89 children. most of the new cases were in parts of southwestern ontario including the city of st. thomas and surrounding counties.

public health authorities aim for 95 per cent of people in a community to be protected from measles to prevent outbreaks, notes the journal vaccine. if that’s not happening, case counts can spiral. as the lancet infectious diseases reports, a single person, on average, infects 12 to 18 people who are susceptible to measles. vaccination rates in canada have dropped to 82.5 per cent, a significant decline seen before, during and after the covid-19 pandemic, attributed to vaccination disruptions during the pandemic and vaccine misinformation online.

impact of measles on canadian society

there is a cost that comes with a measles outbreak that is not just chipping away at peace of mind, but substantial dollars. it has a ripple effect of impacting hospital and public health resources, overtime costs, and translating to missed work or school for people who’ve been told to isolate. what the actual cost is remains to be tallied. studies of previous outbreaks offer insights. one in the american academy of pediatrics estimates a 2019 measles outbreak of 72 confirmed cases in washington state would have cost us$3.4 million.

this figure comes in at $47,479 per case or $814 per contact. the bulk of the collected and estimated expenses were for the public health response. productivity losses accounted for about $1 million, and direct medical costs were under $100,000.

the estimates “indicate that under vaccination can carry a substantial cost for individuals, communities and public health institutions and underscore the value of vaccination,” the study authors wrote.

beyond the short-term expenses, there can be longer-term costs of lower vaccination coverage. for example, infants generally are protected against measles by their mothers’ immune systems until they are eligible for vaccination. unvaccinated children who become unvaccinated mothers leave infants susceptible to disease, and newborns infected with the measles virus are more likely to have complications. this leads to increased financial costs of trying to manage outbreaks.

experts say that about 30 per cent of people infected will have a complication with measles, like bacterial pneumonia, gastrointestinal, and neurologic effects like encephalitis, an inflammation of the brain. there is no specific antiviral treatment for measles infection which basically runs its course with supportive care.

beyond the problem of lower vaccination is the threat posed by the delay between exposure and when measles symptoms appear. this can be followed by a time lag between types of symptoms and explains why those who eventually go for treatment may pass through schools, airports, grocery stores and hospitals before being diagnosed.

resources and support for measles in canada

public health officials stress that vaccination is the best prevention. for children and most adults born after 1970, this means receiving two doses of measles-containing vaccine, like the mmr vaccine. people travelling outside of canada should make sure they are protected through vaccination prior to travelling.

according to the centers for disease control and prevention, those at highest risk of exposure, like an infant or someone who is pregnant, may benefit from a medicine called immune globulin to reduce the risk of developing measles.

for resources and support, visit the following:

in the absence of adequate vaccination, measles remains a serious public health threat. clinical guidance and public awareness are critical for prompt recognition, management, and effective outbreak control, especially when you consider that many healthcare providers are encountering measles for the first time. let’s all step up prevention to help control this disease.

karen hawthorne

karen hawthorne worked for six years as a digital editor for the national post, contributing articles on health, business, culture and travel for affiliated newspapers across canada. she now writes from her home office in toronto and takes breaks to bounce with her son on the backyard trampoline and walk bingo, her bull terrier.