Measles Outbreak: A Growing Concern in Canadian Provinces

Quebec, Ontario, Manitoba, and British Columbia are experiencing a surge in measles cases, raising concerns about public health and vaccination rates. Measles, an extremely contagious disease, can lead to serious complications, especially among babies. “Measles is an extremely contagious disease: only one case can lead to up to 16 others if these people are not vaccinated,” warns Dr. Nicholas Brousseau, a specialist in public health and preventive medicine at the National Institute of Public Health of Quebec (Inspq).

Measles is often referred to as a “spring disease,” with the months of February, March, and April typically seeing the highest activity. This seasonal pattern is one reason for the current increase in cases. “It is also said that measles is a spring disease. Often, it is the months of February, March and April which are the most active, so it is one of the reasons that can explain the higher number of cases currently,” recalls Dr. Brousseau.

The disease can lead to severe complications, including blindness, encephalitis, pneumonia, and in rare cases, death. Last year, a child under five who contracted measles during a trip and was not vaccinated died. This tragic event underscores the importance of vaccination, especially for travelers. The United States has also reported a measles-related death for the first time in ten years, in Texas. “A child of age to be educated who was not vaccinated and who had been hospitalized last week,” the authorities said.

This situation reminds us that measles can lead to complications. It is a serious illness for which a vaccine had to be developed.

In Quebec, the measles outbreak that began in December 2024 has now infected 30 people, with three new cases reported recently. The Laurentides region is the most affected, with 23 cases, primarily among young unvaccinated adults. Montreal, Laval, and Montérégie have also reported cases. “It is not alarming, in the sense that it remains for the moment limited to mainly a region,” adds Dr. Caroline Quach, a pediatrician and microbiologist-infectiologist. However, as long as there are unprotected individuals, the risk of transmission remains high.

In Ontario, health authorities have identified 84 new cases in the past two weeks, bringing the total to 119 confirmed cases and 23 probable cases. Eighteen children were hospitalized, with one requiring intensive care. This surge is particularly concerning given that Ontario had only 101 infections between 2013 and 2023. Manitoba has reported five confirmed cases, all linked to outbreaks in Ontario, and British Columbia has identified a second case.

Public health officials are emphasizing the importance of vaccination as the best protection against measles. “We do not want this disease to settle in our communities. The best protection remains vaccination,” says Dr. Éric Goyer, director of public health in the Laurentides region. Vaccination coverage for primary and secondary students for the current school year is around 90%, but this is not optimal, according to Dr. Quach. “Otherwise we would not have had secondary transmission, so clearly, it is not,” she notes.

“That measles is extremely rare, it is a great victory for public health,” says Dr. Nicholas Brousseau, who expects the situation to return to normal in the coming weeks. However, public health experts remain vigilant, encouraging those who are not adequately protected to consult the list of places frequented by infected persons in recent weeks. All individuals, vaccinated or not, who may have been in contact with the virus should be attentive to the appearance of symptoms.

The First Symptoms of Measles

• Fever
• Nasal congestion with nasal flow
• Cough
• Conjunctivitis (red eyes flowing)
• Eyes sensitive to light
• Generalized discomfort

Redness then appears on the face and body. If you think you have been infected, it is recommended to contact your local health department. The incubation period (between exposure to the virus and the appearance of symptoms) is 5 to 21 days. An infected person is contagious four days before the appearance of symptoms and four days afterward. The infection lasts for one or two weeks.

“We are certainly concerned about vaccination hesitation in the face of this vaccine,” adds Dr. Quach. “If we continue to see that there is a drop in vaccination coverage, especially among young children, which is happening in the United States, will end up happening here.”

In the U.S., measles outbreaks have been a recurring issue, with recent cases in states like New York, California, and Washington. The Centers for Disease Control and Prevention (CDC) has been actively promoting vaccination campaigns to prevent further spread. The CDC recommends that children receive two doses of the MMR (measles, mumps, and rubella) vaccine, with the first dose given at 12-15 months and the second dose at 4-6 years. Adults who have not been vaccinated or are unsure of their vaccination status should also get vaccinated.

The recent surge in measles cases in Canada serves as a reminder of the importance of vaccination and the potential risks of vaccine hesitancy. Public health officials are urging parents and individuals to ensure they are up-to-date on their vaccinations to protect themselves and their communities. As Dr. Brousseau notes, “That measles is extremely rare, it is a great victory for public health,” but ongoing vigilance and vaccination efforts are crucial to maintaining this success.