Step up measles vaccinations, say doctors as outbreaks accelerate in Ontario, Alberta

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Doctors are urging public health officials in Ontario and Alberta to step up vaccination and messaging efforts as measles outbreaks in those provinces continue to grow. 

Ontario reported 223 new confirmed and probable infections of measles over the past week. As of May 2, a total of 210 confirmed measles cases were reported to Alberta Health.

"That's the largest single week increase since the outbreak began in October of 2024," said Dr. Sarah Wilson, a public health physician with Public Health Ontario.

"A lot of important developments in the last week, unfortunately."

The bulk of Ontario's cases are in the Southwestern Public Health region that includes the city of St. Thomas and surrounding counties.

In a sign of how serious measles can be, Public Health Ontario reported 84 people have been hospitalized — including 63 children — during the outbreak. Eight patients were hospitalized in the last week, including seven who needed intensive care, Wilson said.

The vaccine-preventable disease commonly causes fever, cough, red watery eyes and, later, a blotchy rash. 

Because the measles virus is so infectious, it can spread rapidly among those who have not been vaccinated, even if most people in a community are immunized. Public health authorities aim for 95 per cent of people in a community to be protected from measles to prevent outbreaks.

But vaccination rates are nowhere near that in many places, for a variety of reasons — from disruptions caused by the COVID-19 pandemic, to vaccine misinformation proliferating online. 

While current top provincial doctors have said little, or nothing at all, since the outbreak began, one doctor didn't mince words during a recent lecture at the University of Alberta.

"I think there has been a complete failure of leadership at all levels, and there's public complacency," said Dr. Mark Joffe, Alberta's former chief medical officer of health, whose contract ended about two weeks ago.

The Canadian Immunization Guide recommends kids get their first routine dose of measles-containing vaccine at 12 to 15 months of age and the second dose at 18 months but no later than when the child starts school.

Children who aren't yet vaccinated are most at risk, doctors say. The Public Health Agency of Canada says people who are at higher risk of developing severe complications from measles include those who are pregnant, people with weakened immune systems and children who are less than 5 years of age.