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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.
Tackling vaccine misinformation
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.
Measles may start like a bad cold — with symptoms like a high fever and cough — but in rare cases, it turns deadly. For one child, complications emerged about a decade later, robbing her of speech, movement and, eventually, her life.
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.”
Public health messaging is undermined by disinformation, said Dr. Issac Bogoch, an infectious diseases specialist at Toronto’s University Health Network. “We can see disinformation online amplified and it has real world consequences.”
The issue of trust
In Canada, the measles outbreaks in both Ontario and Alberta have been focused in unique, close-knit religious and culturally distinct communities, Saxinger said.
“There’s a lot of trust-building that’s required with some groups of the population,” Saxinger said. “That’s something that there has to be continual investment in, honestly.”
While measles is a disease that can be well-controlled and potentially even eliminated with existing tools, Saxinger estimated half a million people are not immune to measles in Alberta alone, based on vaccination rates and blood tests for antibodies.
Mennonite communities scattered in southwestern Ontario were deeply affected by the province’s measles outbreak.
Catalina Friesen, a personal support worker with the Central Community Health Centre in Alymer, Ont., near London, speaks Low German and works with a nurse practitioner at a mobile clinic to translate during medical visits.
“They won’t come see us if they don’t trust us,” Friesen said. Being part of the community, Friesen said she’s able to understand what families are going through and help them to see the importance of vaccination and preventing spread of measles by staying home when sick.
“I don’t think they’re worried about specifically the measles vaccine. I think they’re just worried about being told what to do when they don’t want to do it.”
Friesen said the mistrust among Mennonites stems from mistreatment over the past 100 years, including offers of autonomy by officials that weren’t followed through.
Calls for vaccine registry
Knowing whether someone is vaccinated for measles would be helpful for doctors and nurses in Ontario hospitals who screen symptoms like fever and rash all the time, said Dr. Jeffrey Pernica, a pediatric infectious disease physician at McMaster Children’s Hospital in Hamilton, Ont.
“It’s not as though doctors at urgent care or the [emergency department] or some other family doctor will know if a given person is vaccinated, which greatly impedes their ability to deliver care.”
Vaccination records in Ontario are currently scattered between individual medical offices that don’t always get shared with local public health units, or may get written on slips of paper that can be misplaced.
When a measles exposure occurs, easily accessible and connected records would also help health-care providers in hospitals who currently have to spend time chasing down information on who has been vaccinated, Pernica said.
“It makes a lot of sense to have provincial vaccine registries that are compatible with one another so we have a national view as to where some of these pockets might be,” said Bogoch, who called it a “no brainer” to have a national vaccine registry for routine childhood immunizations. Ontario’s chief public health officer has also called for a national registry to guide public health responses.
Bowdish, the immunologist, said Canadians who move between provinces and territories would also benefit from less reliance on paper immunization records alone.
“Canadians are a very mobile bunch and many people, myself included, have had vaccines in different provinces,” Bowdish said. “Very hard to track those in provincial registries. Much easier at a national level, right?”
Looking ahead, the massive global measles resurgence makes it “inevitable” that measles will land in Canada again, Bogoch said. To avoid setting off long chains of transmission takes higher vaccination rates.
“Easy to say, but of course it takes time, effort, energy, resources to get that done.”
