Measles cases have been popping up all over the world, including in Canada. This highly contagious virus can be devastating – and even deadly – to people who haven’t been vaccinated against it.
The Globe and Mail’s health columnist André Picard joined The Decibel podcast and spoke with host Menaka Raman-Wilms to explain why we’re seeing this sudden rise and what can be done about it.
(To listen to the episode, find it on the podcast player of your choice using this link.)
What were things like before there was a vaccine against measles?
Back in the old days, when I was a child, measles was a big deal. Everybody got measles, 100,000 people a year in Canada, even though the population was much lower, every child would get measles at some point, some of them would get really gravely ill and some would die. We would have about 50 to 100 deaths a year in Canada, even in the ‘60s when we had relatively good medical treatment.
What is it like to have a measles infection? What happens to you?
Most people who have the measles will have fairly mild illness. They’ll have these telltale red spots that look a little unseemly. The danger is the fever that comes along with this. The fever can cause blindness, deafness and developmental disabilities.
There’s another thing, which we’ve discovered fairly recently, the concept called immune amnesia, where measles damages the immune system, and actually leaves you susceptible to other infections. So once you have measles, you can get all these other childhood diseases more readily. There’s even a form of neurological damage that we know comes back seven or eight years after kids are infected, and it’s deadly. This has long-lasting effects on the body.
How exactly does measles spread?
It spreads really, really easily. It’s airborne. It also sticks around. It’s one of these unusual viruses – you can actually get infected about an hour after someone leaves the room. So it just hangs around on surfaces, in the air. When I was a kid, if there was measles in a class, everybody had measles.
On average, 12 to 18 people will get infected if someone in the room has measles. With COVID-19, it would be one to two people.
If you’re unvaccinated, you’re at risk. But does that mean there’s no risk for people who are vaccinated?
It’s not no risk. It’s not zero, but it’s a really highly effective vaccine, 95 to 97 per cent effective, so it’s very unlikely you get infected if you’re vaccinated. The most fascinating thing about this is that the vaccine works forever. So people who got vaccinated in the 1960s, they still have protection. This is not a virus that mutates the changes. It’s very different from COVID-19. It’s very stable. So anybody who has been vaccinated who’s had their two shots, or who has been infected, they’re pretty well not going to get measles again.
At what age do children get vaccinated for measles?
You get it after age one. You don’t get it before that because your immune system is not developed enough. Children get it as part of the MMR vaccine – measles, mumps, rubella. Then you get a second shot a little later – every province is a little different.
Where are we seeing measles cases popping up in the world?
What we’re seeing it this is mostly a problem in the developing world. Yemen, Azerbaijan, Kazakhstan, India, Ethiopia, those are all the big ones. But then we’re seeing significant outbreaks around Europe, the U.K., France, for example. So lots of places that Canadians travel. The U.S. has a record number of cases as well, mostly concentrated in Florida.
How big of an increase have we seen in measles cases in the last few years?
Measles back before the vaccine killed about 2.6 million, mostly children every year. That dropped steadily after the vaccine right till 2019, where we were down below 90,000 cases. We were talking seriously about maybe this disease can be eradicated because it doesn’t have an animal host. But then during the pandemic, there has been this huge resurgence. So we’re up this year to I think, 136,000 deaths last year and nine million cases that we know of. And that’s a dramatic increase, over two years a doubling of cases.
What’s the measles situation in Canada?
In recent days we’ve seen a jump in cases. As of Tuesday afternoon, we have 17 cases in four provinces. The epicentre seems to be Montreal, there’s 10 cases in the province of Quebec, most in Montreal and the surrounding area. Only three of those cases are linked to travel. So that is very concerning. It tells us that this is spreading, and again, probably more widely than we think.
What’s going on now is happening in multiple places, there’s community transmission in different provinces. We already have more cases this year than we had all of last year.
How concerned should Canadians be about measles?
I think everyone should make sure they’re vaccinated. This is an extremely contagious illness. Once it gets into a community, it can go really fast. The good thing in Canada is we still do have very high vaccination rates. With the very concerning case in York region outside Toronto, we learned that 95 per cent of kids in the high school where the exposure happened are vaccinated, so that’s really good news. But there’s still that 5 per cent that are not vaccinated. Montreal is probably the most concerning. We know that the data published there in some schools, they have vaccination rates as low as 30 per cent. So if the measles gets into a school like that, it can really spread like wildfire.
Why are we seeing so many measles cases right now?
There’s a few reasons. One of them has to do with the pandemic: public health was overwhelmed in much of the world, people were locked down, they were not going to their doctors, etc. So a lot of kids missed their vaccination. That’s what’s happening in the developing world, a huge spread because of unvaccinated kids, people who want to be vaccinated, but they weren’t able to.
Then we have North America, Europe, which is a totally different situation where we have people shunning vaccination for a whole host of reasons. Misinformation, the belief that their immune system is magic, etc. And then they’re getting measles because they’re rejecting the vaccine.
The measles vaccine was falsely linked to autism. How did that happen?
Gastroenterologist Andrew Wakefield published a paper which ended up being exposed as a fraud. In the paper he said people who get MMR vaccine are at a raised risk of autism. This scared a lot of parents. It turned out that the reason he published the paper is because ironically, he had developed his own vaccine, which he wanted to sell. He wasn’t anti-vaccine to begin with. But he’s kind of gone into that camp, and he’s done untold damage.
How exactly does the measles vaccine, which is usually the MMR vaccine in Canada, work?
It is an inactivated vaccine. There’s no real measles virus, it just simulates it. So you trick the body into thinking it’s been exposed to measles, it creates antibodies and then you have this shield up for – in the case of measles – the rest of your life. So it’s pretty simple technology.
What can health officials do to get people comfortable with vaccinating their children?
I think public health, unfortunately, is kind of old-fashioned in its communication ways. They kind of operate like the clergy: we’re going to tell you this is good, and you should do it. And that’s not how modern life operates. They have to engage more, they have to challenge anti-vaccine forces who are very good at communication, who are very organized and they are very self interested – they’re usually selling so-called alternative products to prevent illness, making a lot of money off it. We have to realize why people are doing this. The most unfortunate thing is the most effective way to get people to vaccinate is when there starts to be death, and people see it as a reality. And I hope we don’t get to that. But I think we’re going to see something like that in Florida. The classic public health paradox is that when public health works, people take it for granted.