Hi, I'm Wendy Zuckerman and you're listening to Science Versus.
Today on the show, the insanely weird virus that is measles.
For more than 20 years, the US had stopped the ongoing spread of measles.
Yeah. I mean, we declared it eliminated.
This is Grace Wade, health reporter at New Scientist magazine.
That's the thing, the measles used to be this perfect example of the power of medicine and like the power of vaccines and it was always like heralded as this great example and now we're just watching it like crumble and before our eyes.
On the 20th of January, Texas reported a case of measles and then another one and another one.
The country's deadly measles outbreak is getting worse, spreading at an alarming rate in Texas.
Measles cases connected to the outbreak in Texas have officially passed 500 confirmed cases.
It's gonna get worse before it gets better.
And now, there are infections all over the country, there's a whole rash of cases in more than 20 states.
Some of those are just isolated cases, but in other states, the disease is spreading.
And so that's concerning, right?
Cause you're seeing this outbreak spread to multiple states and then from there, take off.
In some cases, people who were in Texas have then spread the virus to other states.
But not always. Grace said that the outbreak in Michigan started when someone got infected on a trip to Ontario, Canada, where they're currently experiencing a measles outbreak of their own.
In the U .S., at least 800 people have had measles.
That's according to the CDC.
The vast majority of those, 96 % are unvaccinated.
Or we don't know their vaccination status.
800 cases. How many hospitalized?
How many dead? 85 people have been hospitalized.
Two people have tragically died from measles.
They were both unvaccinated children and there was also one other potential death related to measles.
It's still under investigation.
And now, online, there's all these people talking about measles and vaccines.
Oh would you look at that.
After a second child has died of measles… Some say this is bad because measles is so contagious.
While others say that measles isn't such a big deal.
Why are we freaking out here?
There's viral videos where people point out, didn't everyone just get measles back in the day?
You just get a rash, a red rash.
They make it seem like it's such a scary thing.
Yeah, it wasn't no big deal.
And you know, the Brady Bunch kids were fine.
Boy, this is the life, isn't it?
Yeah, if you have to get sick, You sure can't beat the measles.
Meanwhile, the head of Health and Human Services, Robert F.
Kennedy Jr. is saying that part of what's causing this current outbreak is that the vaccine loses its effectiveness over time.
The vaccine wanes. The vaccine's weighing about 4 .8 % per year.
So, you know, that is a leaky vaccine and that problem is always going to be around.
So today on the show, how worried do you really need to be about this US outbreak?
What is measles doing in our body and our brains?
And I'll tell you what, it's weirder than I thought.
And how can we stop these outbreaks in their tracks and possibly even rid the world of measles?
When it comes to measles, there's a lot of...
If you have to get sick, sure can't beat the measles.
But then there's science.
Science vs. Measles is coming up just after the break.
This episode of Science versus is presented by Amazon.
The last thing you want to do when you're sick is go to the pharmacy to pick up a prescription because then you're standing in a long line with a whole bunch of sick people.
And everyone is sick of being sick around other people who are sick.
Amazon pharmacy will deliver right to you, fast, so you can get meds without congregating amongst the contagious.
Healthcare just got less painful.
Amazon pharmacy. This episode is brought to you by Indeed.
Taking things slow isn't always a good thing.
Sometimes, you need to speed things along, like when your toilet breaks down.
You gotta get that plumber in quickly, or you're gonna be in trouble.
If you're hiring, you probably also want to get things moving fast. So use Indeed.
Indeed Sponsored Jobs move your job post to the top of the page helping you stand out and reach candidates quickly.
Speed up your hiring right now with a $75 Sponsored Job Credit at indeed .com slash science on.
That's indeed .com slash science on.
Terms and conditions apply.
Hiring Indeed is all you need.
Welcome back, today on the show, Measles.
Our first question is, how serious is this illness really?
Because the majority of folks who get measles will recover fairly quickly.
At first, you'll probably notice flu -like symptoms, coughing, sneezing, fever.
This is because measles is a respiratory virus.
A couple of days later, you might see these tiny white spots inside your mouth – they're called Coplix spots – and then, of course, there's that blotchy red rash, which – fun fact – is triggered by the measles virus infecting your skin cells.
In the current outbreak in the U .S., hundreds of folks who have gotten infected, almost 90 percent, were never hospitalized.
So you can understand why people are saying, what's the big deal here?
But the thing is, even if you get a mild case of measles, what researchers are realizing is that this virus is actually doing something pretty weird that could have consequences on your health for years to come.
Measles is really nasty.
This is Peter Casson.
He's a professor who studies viruses at Georgia Institute of Technology.
Most people think about measles, and they think of it as a mild disease that is quickly over and quickly forgotten, that this is not some benign childhood rash.
Peter told me that researchers have known for a while now, that after young kids get the measles and get over it, they're more likely to contract other infectious diseases afterwards.
So things like colds and flus.
And sometimes this can actually get so bad that the kids get hospitalized.
And so this idea emerged that maybe measles is going after your immune system, or what Peter calls Immunological destruction and there was a particularly striking study a few years ago.
It all started when there was this outbreak of measles in an orthodox Protestant community in the Netherlands.
This is a tight -knit community that isn't so crash -hot on vaccines.
And so during this particular outbreak, researchers took blood samples from 82 kids who hadn't been infected yet.
They then followed the children.
93 percent of them ended up getting measles.
Under half of those had a mild case.
The others were pretty severe.
On average, seven weeks after the kids got infected, the researchers took blood samples again and they basically wanted to know how exactly was measles messing with their immune system.
So as part of the study, they zoomed in on these immune cells that make antibodies.
I talked to Peter about them.
These are the immune cells that, you know, if you've been infected with a cold before or the flu, or COVID, you have cells that remember this infection so that hopefully next time you get it, either you won't even feel symptoms because your immune system will kill it so quickly.
They'll say, Oh, I remember this enemy, I know how to kill it, or the disease will be much milder the second, third time around.
Or if you've gotten a vaccine, these are the cells that that make you immune to whatever you're vaccinated against. and this study on the Dutch outbreak, it was specifically looking at whether measles affected something called the antibody repertoire.
You can think of it almost like a little library of antibodies that your immune system makes against the infections that you've had.
What they found is that unvaccinated kids who got measles, on average, they lost around 20 percent of their antibody library.
But there was this huge range.
In the worst case, it raised more than 70 percent of a kid's repertoire.
What does this mean?
Next time you get infected with the cold, the flu, COVID, what - As if you had never seen it.
It's as if it's the first time that wipes out a lot of the old memories.
It depends. If measles has completely wiped out that part of her repertoire, it's as if you've never seen it.
if it got part of it, but not all of it, it's somewhere in between.
But that's one insidious feature of this.
You can think about it like a computer virus that's getting into your hard drive and deleting all of these programs that help you fight off infections.
Some papers even call this immune amnesia.
This immune effect where measles is killing off your antibodies, This happens to some extent to everyone who gets a measles infection.
This is not just for complicated, serious cases.
This is basically...
It's not just for complicated, serious cases.
It's common. I can't say universal.
But it's extremely common. Wow, when you read that paper, what did you think?
I thought, this is bad stuff, to be honest. Now Peter told me that if you are Unvaxxed and you do get measles, your immune system isn't screwed for life, but you'll probably need to get exposed to all of these viruses and bacteria, the colds, the flus again, to start building that antibody library back up.
To go back to our hard drive analogy, it's like you've got to boot up the old computer, reinstall those missing programs, kind of one by one.
And this could take months or even years to get back to where you were.
Scientists are still trying to work all of this out.
But still, this is what we know about a so -called mild measles infection.
And then there's the more serious cases.
In the current outbreak, around one in 10 people have been hospitalised.
And so I asked Dr. Maru Sheel from the University of Sydney in Australia why exactly a measles infection might land you in the hospital.
Like, what is it doing that's so bad?
And she said that the most common complication is actually pneumonia.
So pneumonia is basically when you get a really bad infection in your lungs and you can't breathe.
The breathing becomes so hard, you just you can't get oxygen into your body.
And it's probably the most common cause of death as well from measles in young children.
In fact, one of the kids who died in Texas in the current outbreak, and an 8 -year -old girl died from lung failure.
And it is expected that roughly 1 in 500 children who get measles will die from it.
In around 1 in 1000 cases, measles can cause encephalitis, which basically means that you get all of this inflammation in your brain and your brain swells up.
This can lead to convulsions, it can lead to child death, or with intellectual disability.
And encephalitis is actually another reason that you can die from measles.
And then there's some really rare, but really weird stuff that measles can do.
I talked about this one thing with Meru.
I read that it's possible in rare cases, maybe less than one in 10 ,000, that the measles virus can get into the brain.
The virus itself gets into the brain and can almost learn how to infect the brain.
What essentially happens is you get infected with measles, you've recovered, and then the virus can essentially stay in your body undetected.
And then seven to 10 years later, it can get reactivated and attack your nervous system, can lead to progressive dementia, and almost always is fatal.
I read this case report of a 16 -year -old boy who came into a medical center because he had been feeling weak, he was having some bladder problems. 16 -year -old kid lost his balance and then started having seizures, and the doctors worked out that it was this condition, it was from a measles infection that he got when he was two months old.
So it had been sitting in his body, in his brain for 16 years and then he did end up dying from it.
That is so terrifying, it's so terrifying.
It's absolutely terrifying and it's a rare complication but no one wants to get it.
Robert F. Kennedy Jr., who's the Health and Human Services Secretary, said it's very difficult for measles to kill a healthy person.
The best thing that Americans can do is to keep themselves healthy.
It's very, very difficult for measles to kill a healthy person.
Is that true? Generally, with most viral infections, most people will recover.
Now, if you are immunocompromised, you're sick, pregnant, or you're a little baby, thanks for listening to this podcast, you are at a greater risk of having a nastier measles infection.
We also know that the measles death rate is higher in certain developing countries, where you might have worse healthcare and some kids might be malnourished.
But Muru told us that even if that's not you, there's no guarantees here.
But we just don't know whether you will recover quickly or whether you'll end up getting hospitalized and dying from measles.
Yeah, the two children who died from measles in the US, I think they were healthy, had no known underlying conditions.
Yeah. And in most people, we want to know those underlying conditions.
You don't know that until something happens.
And yeah, these, to my knowledge as well, these two children who died were healthy.
They were just unvaccinated children, and that could have been prevented.
So, is measles scary?
Are we overreacting with this current outbreak in the US?
You decide. In the US right now, we've got around one in 10 hospitalized, at least two out of 800 dead, and it's hitting kids particularly hard. And even if you get measles and bounce back straight away, it could muck about with your immune system, making it weaker for a while, and putting you at a higher risk of other nasty infections.
Now, let's look at how contagious measles is, because one thing that you hear over and over again is that it's extremely contagious.
So what are we talking about here?
And for this, I spoke to infectious disease researcher Dr. Catherine Gibney at the Doherty Institute in Melbourne, Australia.
And she said that all the hype that you read about measles being infectious, it's not hype.
It is the infection that you think of that is the most contagious virus that we know of.
It's a big claim to fame.
So, if you've got a room full of unvaccinated people, someone walks in with measles, how many of those others would get infected?
Yeah, so they say that nine in 10 people will be infected if they're exposed.
Another way to look at it is, do you remember the R naught number from COVID?
It's basically the number that says, if you are walking around infected with a disease, on average, how many other susceptible or unvaccinated people will you infect?
So, the beginning of COVID it was sort of 1 .5, 2 .5.
For flu it's like 1 to 2.
For measles it's 12 to 18.
Wow. And flu is only 1 to 2.
I mean we're going into a flu season now.
So it's interesting that's only 1 to 2 and measles 12 to 18.
Yeah. So it's just on another scale.
So yeah, compared to a lot of other diseases out there, measles is pretty R -naughty.
Here's how Maru thinks about it.
It's one of those viruses that it finds any gaps.
We often call it, when we're studying epidemiology, we call it the tracer disease.
It's the canary in the coal mine.
If you have a gap in your immunisation coverage, it will find that gap.
So, why is measles on another scale?
Why does it spread so easily?
Well, researchers told me that one thing that's going on here is that you're actually very contagious in the days before you even know you have measles, like before you start getting obvious symptoms. But that's not all.
Maru told me that this virus is also hearty as fuck.
I mean, she didn't put it quite like that.
Because it's an airborne virus, so essentially measles, if somebody is breathing is contagious and breathing measles virus, the particles in the air will pick it up and they linger for about up to two hours after a person has been there.
So if I went into a bar being infectious and I left within half an hour, and someone came in an hour later it's possible that they might get exposed to that air and they can still potentially catch it.
That is insane. That is up to two hours.
On top of all of this, Catherine told me that you don't need to breathe in that many measles viral particles to actually end up sick, particularly when you compare it to something like COVID.
This thing is seriously relentless.
It's like the John Wick of viruses.
You can't hide from it.
I read about this report from the 1991 what they called back then the special Olympics where there was an outbreak of measles and it was the athletes where the outbreak had happened and they tracked two spectators, got infected and they were sitting in the upper decks, 32 metres away.
These are the reports that make us all very nervous about measles.
So measles is looking like one tough opponent but after the break, we fight back.
Today's ask Wendy, me, anything is brought to you by Amazon, whether it's delivering medication to your door with Amazon pharmacy or 24 -7 virtual care with Amazon One medical.
Thanks to Amazon Healthcare just got less painful.
So I'm here with senior producer, Rose Rimler, who has some questions for me from you guys, from our listeners.
Yes. So the first one comes from Kaylee on Instagram.
She asked, what's the weirdest question you've had to ask a stranger for science, of course?
Um, a lot of them are a little bit not safe for branded advertising.
But maybe one of the most awkward was when we were at the human composting facility and we were looking at this big tub of human compost and I really wanted to put my hands in it.
And I said, can I please touch that?
Can I touch it? And they said yes!
And our next question comes from Steve, also on Instagram.
He asks, tell us about some episodes that were left on the cutting room floor because they came to the wrong conclusion.
Wrong conclusion. Interesting.
OK, I really like this question, Steve, thank you for asking it, because I feel like we get actually a lot of people sort of asking us this in this world where science has become so politicized.
I think sometimes we get accused, if that's the right word, of being politicized ourselves or only delivering woke science, if you want.
But actually, when it comes to pitching for science versus, the more surprising that the science is, the more likely the episode is to get through.
For those who do sort of think we have become a slave to the...
To the woke mob? Yes, we actually piss off a lot of people by really focusing on the science and just reporting on what we see.
And so just to some examples where I would say we did get to the quote unquote wrong conclusion according to certain pockets of the internet.
In the menopause episode, according to menopause social media, saying that hormone therapy increases your risk of breast cancer even slightly.
That's the wrong answer.
A lot of people are saying that hormones are magic.
So that was the wrong answer.
Our recent episode on fluoride had some quote unquote wrong answers by saying that the science here is actually more messy than we thought it was.
So I guess, in a nutshell, no, we do not leave episodes on the cutting room floor because they come to the wrong conclusion.
We deliver the science and that's why you come to us.
Yeah, I mean, I think a lot of our episodes come to some conclusion that is the opposite or more nuanced than sort of the darling thesis of some group of people, including people that have very strong feelings on either side of the political aisle.
Yeah. Thanks, girls.
Thanks, Wendy. Today's Ask Wendy me Anything was brought to you by Amazon.
Thanks to Amazon, healthcare just got less painful.
This episode is brought to you by Indeed.
Making sure you have the right people for the job is essential.
If you're going in a plane, you hope that a pilot is the one flying it.
When it comes to hiring the right people for your business, Indeed is all you need, because they can help you find qualified talent quickly.
Indeed's sponsored jobs help you reach relevant candidates faster, with 45 % more applications on sponsored jobs than non -sponsored jobs, according to Indeed data.
Plus, you're only paying for results.
With Indeed sponsored jobs, you don't have to worry about getting sucked into monthly subscriptions or long -term contracts.
There's no need to wait any longer.
Speed up your hiring right now with Indeed.
Listeners of this show will get a $75 sponsored job credit to get your jobs more visibility at Indeed .com slash science on.
That's Indeed .com slash science on right now.
Support our show by saying you heard about indeed on this podcast. Indeed .com slash science on.
Terms and conditions apply.
Hiring? Indeed is all you need.
Welcome back. Today on the show, measles, it's very contagious, but we have one weapon against it, the vaccine.
And it works well. With two doses, according to the CDC, the MMR or measles, mumps, and rubella vaccine is 97 % effective.
So essentially it's almost close to 100%.
It's pretty amazing vaccine against measles.
That's Dr. Maru Shield again, an infectious disease researcher.
Now, concerningly, RFK Jr recently said that one of the reasons that people are now getting measles in the U .S. is because the vaccine is leaky and its effectiveness wanes over time.
Is that true? I don't think leaky is the right way to describe it.
There is a little bit of emerging evidence that there is some decline in your antibody levels over the years from vaccination, but it's so minuscule.
So it's not like you're going to zero after that.
There might be a little drop in your antibody levels.
Right. I mean, just by virtue of the fact when you look at the numbers of the current outbreak in the US, if the measles vaccine was leaky and its effectiveness waned over time, you would expect way more vaccinated people to be infected, right?
Yeah, that's right.
So most of the cases globally and in the US are in unvaccinated people.
According to the CDC, in the current US outbreak, only two percent of those who have been infected were fully vaccinated.
So this vaccine, it still works.
The fact that it works so well takes us to this amazing possibility when it comes to measles.
What is super interesting to me that I had no idea about before doing this episode is that Measles doesn't infect other animals.
It doesn't have a reservoir in birds or pigs or pangolins or bats or anything.
And so that means we could potentially eradicate measles.
Yeah, absolutely. So when you think about, say, rabies virus, much more difficult, dogs carry it and they can infect humans, but measles on the other hand, is humans are the only natural host for this virus.
And if you get infected and if you are vaccinated, you get an immune response that protects you your entire life, by and large.
Measles virus is quite a stable virus.
It's not mutating like COVID is.
So we've been using basically the same vaccine for decades now.
Working great. More than 50 years.
50 years. And out of last year, there was a study that showed vaccination has prevented or averted 154 million deaths over the last 50 years, most of which are attributed to measles.
Wow. So the vaccine works.
We have this vaccine that works amazingly well over decades.
There's no animal reservoir.
Why haven't we conquered measles yet?
Well, because a lot of people around the world don't have access to the vaccine.
And then a lot of other people who do have access aren't vaccinating their children.
And a big reason why is that they're worried about the risks here.
And you know, this vaccine, it is made by taking the measles virus and then weakening it.
And we basically inject this weakened virus into people.
That's what creates this great immune response.
But some worry that injecting a virus into an otherwise healthy kid is a bad idea.
And you go online and people have all sorts of things to say about how dangerous this vaccine can be.
The truth is that there are a couple of real risks, and then there's a lot of crap online you don't have to worry about.
So, first, some kids might get a rash soon after the vaccine.
Does it look like the measles rash?
what kind of rash? It is a similar red rash.
Oh interesting. But it's very weak, it's not like doesn't spread across the whole body, it's not as deeply red, it might just be a few spots, it might be a milder rash as well.
But important for people to know because that would be quite scary if you weren't expecting it, you give your kid the measles vaccine and all of a sudden they're getting a measles rash.
Absolutely but that Is pretty self -resolving and it'll go away in a few So in about one in three thousand cases, to about one in four thousand cases, a kid may get what's called a febrile seizure after getting the MMR vaccine.
Those figures come from the CDC.
Dr. Catherine Gibney told me that this does not mean measles is infecting your brain or anything.
This happens because after you get a vaccine, it's pretty common to get a fever.
and in young kids that can trigger a seizure.
Is just anytime you get a fever, you could get a seizure.
Yeah, that's right yes.
And particularly for young children.
How serious are those?
They seem scary. Yeah, I think they're scary rather than serious.
And by that, Catherine means that, if you're a parent watching this happen to your kid, it can be really frightening.
But, according to the CDC, nearly all kids will recover quickly.
When we think about sort of vaccine scepticism, I guess we should talk about autism?
Do we have to? Does it lead to autism?
No, definitely not.
So that's been well and truly disproven and very carefully disproven with lots of really great science.
I don't mean to sound dismissive here and I am still seeing a lot of stuff online connecting this vaccine to autism, but the thing is over and over again, studies have compared thousands of kids, in some cases hundreds of thousands of kids, that looked at those who've gotten the vaccine and those who didn't and they can't see higher rates of autism in the kids who got the MMR vaccine.
Next question, what will it take to stop the outbreak in the US?
I talked about this with Maru.
So according to the World Health Organization to prevent outbreaks, we need to vaccinate 95 % or more of the population with two doses.
When we look at the situation in the US, it's been reported that one county in Texas where there's an outbreak, the MMR vaccination rate is 82%.
And then when you look across the US, MMR vaccination rates aren't great in some states like Wisconsin, Alaska and Idaho.
The number of kindergarten kids with two doses of MMR vaccine is less than 85 percent.
Given these numbers, how do you see this all playing out?
Yeah, I think it's tricky to know at the moment where we're headed, but I suspect that with those coverage rates that you've just talked about, Wendy, the outbreak has spread from Texas to multiple states, it's likely that we're going to keep seeing this increase in number of cases, until there is some very quick vaccination.
It's the only way to stop this outbreak is to vaccinate at mass and at speed.
It's like it's rapid fire.
And remember, after you vaccinate, you need about three to four weeks for the immune response to kick in.
I mean, given, I was just looking at the news, and the messages coming from RFK Junior and that sort of thing, and There's been really big cuts to the CDC and public health in general.
If that's what it takes, as someone, Maru, who's been tracking outbreaks around the world, if that's really what it takes, mass vaccination to stop it, that's really the only thing at this point.
Vaccination is the only way to control this outbreak.
We've talked a lot about the US situation, where hundreds of people have been infected.
When it comes to measles around the world, what's going on?
Sadly, measles has been going up for a fair few years now.
The number of cases of measles in Europe have reached numbers they haven't seen in about two decades.
A record spike in measles cases in Europe has killed 37 people since the beginning of 2018.
2018, 2019, there were large outbreaks across Europe as well, more than 90 ,000 cases.
Wow, 90 ,000 across Europe.
Jeepers. Huge huge outbreak.
So from the year 2022 to 2023, so a year and a bit ago, measles cases increased worldwide by 20 percent.
So from about 8 .5 million to about 10 million in 2023.
Wow. Measles is alive and well around the world.
I mean, we are not even close to eradicating this.
Yeah, Vietnam 40 ,000 cases in the most recent outbreak.
That's what they're reporting at the moment.
It's crazy that we thought we were done with measles.
I mean, who are we kidding?
We're not done with measles.
We should be and we could be done with measles, but we're not there yet.
2025 is now the worst year for measles in Canada.
An urgent warning from health officers.
The disease is making a comeback.
Yemen is witnessing a rise in suspected measles cases amongst its children.
Zimbabwe's measles outbreak.
Zambia's been experiencing the current measles outbreak.
Health officials are warning of further outbreaks of measles across the country.
That's science versus measles.
This episode has 98 citations in it.
So if you want to learn more about measles or the vaccine, the MMR vaccine, then just go to the show notes of the podcast and click on the link to the transcript, and you can see everything there.
We'd love to hear how you felt about this episode.
You can find me on TikTok.
I'm at Wendy Zuckerman or we're on Instagram, Science underscore vs. This episode was produced by me, Wendy Zuckerman, with help from Michelle Deng, Merrill Horne, Rose Rimler and Aketi Foster -Keyes.
We're edited by Blythe Turrell.
Fact checking by Eva Dasher.
Mix and sound design by Bobby Lord. Music written by Emma Munger, So Wylie, Peter Leonard, Bumi Hidaka and Bobby Lord. A special thanks to the researchers who helped us with this episode, including Professor Rick Desfart.
And a big thanks to Joseph Lavelle Wilson and the Zuckerman family.
Science versus is a Spotify Studios original.
Listen to us for free on Spotify or wherever you get your podcasts.
If you are listening on Spotify, you can follow us and tap the bell icon so you get notifications when new episodes come out.
And whatever app you are listening on, we would love if you gave us a five star review because it helps people find the show.
I'm Wendy Zuckerman, back to you next time.
