With cases of measles on the rise in Ontario, Halton doctors are asking residents to be proactive ahead of March break to prevent the spread of the dangerous disease during one of the province’s largest outbreaks in recent years.
Measles is an infectious disease that may cause coughing, runny nose and the characteristic measles rash and can be dangerous to young children who catch it, with one in ten kids being sent to the hospital after a measles diagnosis.
“Measles is one of the most infectious diseases we’ve ever known,” Dr. Patrick Galange, Associate Medical Officer of Health at Halton Region Public Health, said. “To put it into perspective, if you have measles and there were ten people around who weren’t vaccinated, nine out of those ten would get it. It’s a very contagious, infectious disease that quickly passes from person to person.”
The infection can spread to various parts of the body once an individual is infected, and can cause other serious conditions like pneumonia or encephalitis if it spreads to the lungs or brain and can even lead to blindness, deafness or death in some cases.
Pregnant women and immunocompromised individuals are also at high-risk of complications from measles.
Public health officials are particularly concerned about diseases like measles around March Break when many families choose to travel while their children are out of school.
“In addition to vaccine hesitancy, this large outbreak that we’re seeing is also because people are starting to travel again,” Galange said. “People may be travelling who are underimmunized and visit somewhere where measles is more prevalent and end up bringing it back to Canada, which spreads it to the non-immunized here.”
The number of measles cases has been rising in Ontario and Halton in recent years. The province averaged between seven and 22 cases per year between 2013 and 2023, but jumped to more than 60 cases in 2024 and over 100 in the first few months of 2025 alone.
“Number one thing, get vaccinated,” Galange said. “Any measles-containing vaccine is extremely safe, extremely well-studied and extremely effective at preventing people from getting measles. It’s a two-dose schedule, with the first dose being up to 95 per cent effective and the second can make you nearly 100 per cent safe.”
Galange also urged Halton residents to be aware of their vaccine status, as Ontario does not have a central vaccine registry for doctors to reference, and to report their vaccination to Public Health Halton .
Canada declared measles to be eradicated from the country in 1998, but a decrease in immunization in recent years has allowed it to return in force.
“Vaccine hesitancy is a big challenge,” Galange said. “It’s always been floating around, but post-pandemic we’re seeing a lot more of it and the measles vaccine falls under that. People might feel more complacent since we don’t see it much anymore, but it’s a catch-22 because the reason we saw so little of it, was due to immunization. If we stop getting immunized, that’s going to change.”
Ontario has seen a decrease in people receiving their second dose of the measles vaccination since the COVID-19 pandemic started.