Measles, also called rubeola, is a very contagious viral illness that causes a distinct rash, fever, and cough. It is so highly contagious that approximately 90 percent of people exposed to measles who are not immune to the virus will develop a measles infection.
Canada was formally declared measles-free in 1998, an achievement credited to high vaccination rates. However, an outbreak of measles began in the Eastern part of Canada in October 2024. In the wake of a measles outbreak in Canada that has infected thousands of people over the past year, an international health agency revoked the country’s measles-free status on Nov. 10, 2025. The Pan American Health Organization made this announcement after the agency’s measles elimination commission met in Mexico City to review the latest public data.
Measles is highly contagious, and a drop in childhood vaccination rates in Canada and in other countries has left many children unprotected from the disease. Not only Canada, but the U.S. has also had large outbreaks of measles this year. Measles is one of the most contagious diseases on the planet. Before the measles vaccine was licensed for use in 1963, nearly every child got measles infection and more than 2 million children died from measles each year.
Canada lost its measles-free elimination status because the percentage of 2-year-olds who have received at least one dose of measles vaccine dropped from about 90% in 2019 to about 82% in 2022 and 2023. As the number of unvaccinated people in the population increased, the risk of measles outbreaks grew. After having only 16 total cases of measles nationwide between 2020 and 2023, the number of measles cases in Canada jumped to more than 100 in 2024 and more than 5,000 cases in 2025. Cases have occurred among infants, children and adults in every Canadian province in 2025, and two infants have died. It is also likely that the U.S. and Canada may lose their measles free elimination status as well because both countries have been exposed to several outbreaks of measles since 2025.
