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A year has passed since measles began sweeping Canada, the outbreak has subsided, but the virus shows no signs of being eradicated.
This week the World Health Organization and Pan American Health Organizationsaid measles has made a “global comeback”, with Canada now reporting the highest total number of cases in the Americas region.
The Public Health Agency of Canada said it considers Oct. 27, 2024, to be the start of an outbreak involving more than 5,000 confirmed and probable cases of the highly contagious airborne measles virus. Two deaths from this outbreak, one in Ontario and one in Albertaoccurs among infants born prematurely who become infected with measles in the womb.
Although Canada has achieved measles elimination status in 1998Doctors fear it will lose that status and join the ranks of places where it has a persistent presence, currently at a low level.
“It's important to think about who else is on this list,” said Dawn Bowdish, a professor at McMaster University School of Medicine and an immunologist. “Places in the world that are experiencing wars, major civil unrest, or lack public health infrastructure.
“The presence of a country like Canada on this list is frankly shocking.”
Of course, preventing any disease forever is difficult because international travel will continue to reintroduce the measles virus into Canada.
But doctors say there are other problems here at home – from mistrust of health workers in vulnerable communities to broader misinformation about vaccines – could pave the way for future outbreaks. That's what they'd like to see change.
Combating vaccine misinformation
The pan-Canadian outbreak began when an international traveler attended a wedding in New Brunswick last October, sparking a smoldering ember of cases that emerged in Ontario, Manitoba, Quebec, Alberta, Saskatchewan, Prince Edward Island, the Northwest Territories, Nova Scotia and British Columbia, primarily among unvaccinated communities, health officials say.
In Canada and around the world misinformation about vaccines threatens immunization efforts.
The measles, mumps and rubella vaccine has been studied “back and forth and sideways in terms of safety,” said Dr. Lynora Saxinger, an infectious disease specialist at the University of Alberta.
Measles may start out as a bad cold – with symptoms such as fever and cough – but in rare cases it can be fatal. One child developed complications about ten years later that robbed him of speech, movement and, ultimately, life.
But persistent, well-orchestrated misinformation campaigns about the measles vaccine have left some people feeling fearful, which Saxinger called a shame. Countering these campaigns will require a concerted effort, such as hiring people to make whistle-blowing videos instead of health workers volunteering to do it informally, she said.
“There's also a need to take a critical look at algorithms and how social media shapes misinformation, and whether there's some kind of amplification of misinformation that needs to be looked at through that lens.” [a] legislative lens, what has been done in Europe“
Misinformation is undermining public health messaging, said Dr. Issac Bogoch, an infectious disease specialist at the University of Toronto Health Network. “We're seeing misinformation on the rise online, and that's having real-world consequences.”
Question of trust
In Canada, measles outbreaks in both Ontario and Alberta were concentrated in unique, close-knit religious and culturally distinct communities, Saxinger said.
“There needs to be some serious trust-building with certain populations,” Saxinger said. “Honestly, this is something that needs to be continually invested in.”
While measles is a disease that can be well controlled and potentially even eliminated using existing tools, Saxinger estimates that half a million people are uninsured for measles in Alberta alone, based on vaccination rates and antibody blood tests.
Mennonite communities are scattered throughout southwestern Ontario severely affected by the measles outbreak in the province.
Catalina Friesen, a personal support specialist at the Central Community Health Center in Alymer, Ont., near London, speaks Low German and works with a nurse practitioner in a mobile clinic, interpreting during doctor's visits.
“They won't come to us if they don't trust us,” Friesen said. By being part of the community, Friesen said she can understand what families are going through and help them understand the importance of getting vaccinated and preventing the spread of measles by staying home when sick.
“I don't think it's the measles vaccine that they're worried about. I think they're just worried about being told what to do when they don't want to do it.”
Friesen said mistrust among Mennonites stems from mistreatment over the past 100 years, including sentences autonomy officials who were not signed through.
Call for Vaccine Registration
Knowing whether someone has been vaccinated against measles would be useful for doctors and nurses in Ontario hospitals who are constantly checking for symptoms such as fever and rash, says Dr. Jeffrey Pernica, a pediatric infectious disease physician at McMaster Children's Hospital in Hamilton, Ont.
“This does not mean that emergency room doctors or [emergency department] or some other family physician will know whether the person is vaccinated, which will significantly limit their ability to provide care.”
Vaccination records in Ontario are currently scattered among individual health units and are not always shared with local public health units or may be written down on pieces of paper that can be lost.
In the event of a measles infection, easily accessible and linked records will also help health care workers in hospitals, who currently have to spend time searching for information about who has been vaccinated, Pernicki said.
“It makes a lot of sense to have provincial vaccine registries that are compatible with each other so that we have a national understanding of where some of these hotspots might be,” said Bogoch, who called creating a national vaccine registry for routine childhood immunizations a “no-brainer.” This was stated by Ontario's chief public health officer. also called for a national registry to guide the public health response.
Bowdish, the immunologist, said Canadians who move between provinces and territories would also benefit from relying less on paper vaccination records alone.
“Canadians are a very mobile group and many people, including myself, have been vaccinated in different provinces,” Bowdish said. “It is very difficult to track those who are on provincial registries. It’s much easier at the national level, isn’t it?”
Looking ahead, the large global resurgence of measles makes it “inevitable” for measles to return to Canada, Bogoch said. To avoid creating long chains of transmission, higher levels of vaccination are required.
“It’s easy to say, but of course it takes time, effort, energy and resources to do it.”
