Canada's measles outbreak control challenged by disinformation and distrust, doctors say

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A year since measles started raging in Canada, the outbreak's subsided, but the virus shows no signs of being stamped out.

This week, the World Health Organization and Pan American Health Organization, said measles has made a "global comeback," with Canada currently reporting the highest total number of cases in the Americas region. 

The Public Health Agency of Canada said it considers Oct. 27, 2024 the starting part of an outbreak that's hit more than 5,000 confirmed and probable cases of the highly contagious measles virus that spreads in the air. Two deaths in this outbreak, one in Ontario and one in Alberta, occurred among babies who were born pre-term and got measles in the womb.

While Canada achieved measles eradication status in 1998, doctors are on tenterhooks over the possibility it will lose that status, and join the ranks of places where it’s consistently present, currently at low levels.

"It's important to reflect on who else is on that list," said Dawn Bowdish, a professor in McMaster University’s medicine department and an immunologist. "Places in the world that are going through wars, major civil disruptions or don't have public health infrastructure. 

"To have a country like Canada on that list is frankly shocking."

To be sure, keeping any disease out for good is tricky as international travel will continue to reintroduce measles virus in Canada. 

But doctors say other problems here at home — from distrust of medical officials in vulnerable communities, to broader vaccine disinformation — could set the stage for future outbreaks. Here’s what they’d like to see change.

The pan-Canadian outbreak started when an international traveller attended a wedding in New Brunswick last October, sparking embers of cases that landed in Ontario, Manitoba, Quebec, Alberta, Saskatchewan, Prince Edward Island, the Northwest Territories, Nova Scotia, and British Columbia, mainly among unvaccinated communities, health officials say. 

In Canada and worldwide, vaccine misinformation threatens immunization efforts. 

The measles, mumps and rubella vaccine has been studied "backwards, forwards and sideways in terms of safety," said Dr. Lynora Saxinger, an infectious diseases specialist at the University of Alberta.

But persistent, strongly organized disinformation campaigns about the measles vaccine have left some people feeling scared, which Saxinger called a shame. She said countering those campaigns will take concerted effort, like hiring people to make debunking videos, instead of health professionals volunteering to do it informally. 

"There also needs to be a bit of a critical look at algorithms and how social media is shaping disinformation and whether there's some amplification of disinformation that needs to be looked at through [a] legislative lens, which has been done in Europe."