Ontario urging measles vaccinations amid worst outbreak in more than a decade

The current measles outbreak in Ontario is the most severe the province has seen in over a decade, with 350 reported cases since late October. Dr. Kieran Moore, the province’s chief medical officer of health, is urging Ontarians to ensure they are immunized against the measles to prevent further spread of the highly contagious virus.

According to Dr. Moore, over 96 percent of cases in Ontario are among individuals who are unimmunized or have unknown immunization status. The majority of infections are concentrated in the southwestern part of the province among unvaccinated individuals. It is crucial for everyone to work together to mitigate the spread of this vaccine-preventable disease.

The measles, mumps, and rubella (MMR) vaccine has been in use for over 50 years and is proven to be one of the safest and most effective vaccines available. Children who receive two doses of the vaccine are nearly 100 percent protected, while a single dose provides roughly 95 percent protection. The MMR vaccine is typically administered between 12 to 15 months of age, with a booster given at four to six years old.

Public Health Ontario data shows that only 70 percent of seven-year-olds were fully vaccinated against measles in the last school year, representing a significant decline from pre-pandemic vaccination rates. The National Advisory Committee on Immunization recommends a 95 percent vaccination rate to ensure Canada remains free of endemic measles.

The current outbreak in Ontario is connected to an interprovincial outbreak first reported in New Brunswick, which has also spread to Manitoba. Most of the cases are concentrated in the Southwestern Public Health region and neighbouring Grand Erie. However, the virus has also spread to areas like Windsor and Niagara, hundreds of kilometers away from the initial outbreak.

Measles can lead to serious health complications, including pneumonia, respiratory failure, swelling of the brain, and in rare cases, death. It is essential for everyone to ensure they are immunized against the measles to protect themselves and prevent further spread of the virus.