The Summer Vaccine of the Future
Speaker 1: Science journalist Cassandra Willyard has written a lot about Lyme disease over the years. So when her seven year old daughter was recently bitten by a tick, she went into action mode.
Speaker 2: And I couldn’t totally tell whether it was a blacklegged tick or whether it was a wood tick because it was so little. But I thought, Oh, it’s really little. And it sort of looks like a black Leggett tick to me.
Speaker 1: A black legged tick, also known as a deer tick, is the kind of tick that can carry Lyme.
Speaker 2: And so I pulled it out. I have a little device called a tick key that’s meant for pulling them out, and I. I thought, you know, I just don’t want to worry about it. And so I shipped the tick off to a lab where they assess whether the tick carries the Lyme bacteria or not. And it was clean, so it was all good.
Speaker 1: I spend a lot of time in the Catskill Mountains and there are a lot of ticks there and there and there’s a decent amount of Lyme there and it is not at all uncommon for us to pull a tick off of someone, some member of the family, and I actually put it in a little baggie and put it in the freezer should we need to ship it off to a lab. So hearing that you did that. I’m like, okay, yeah, that sounds normal.
Speaker 2: Yeah.
Speaker 1: And if that sounds extreme to you, it’s worth considering what Lyme disease can do, especially if you don’t catch it early.
Speaker 2: So if you get Lyme disease and you don’t get antibiotics for it and don’t treat it, then you can have things like headaches and neck stiffness. You can sometimes get rashes on other areas of your body. A lot of people complain of of joint pain in their joints or swell just sort of pain in your muscles and tendons and bones, heart palpitations. It’s it’s nasty.
Speaker 1: Right now, my dog can get vaccinated against Lyme, and she has, but I can’t. The last human Lyme vaccine was pulled from the market 20 years ago, but that might be changing as Lyme cases increase, thanks in part to climate change. A new vaccine is in late stage clinical trials. It could be available as soon as 2025.
Speaker 1: So today on the show, Cassandra is going to tell the story of why it took so long to get to this point. I’m Lizzie O’Leary and you’re listening to what next TBD a show about technology, power and how the future will be determined. Stick around.
Speaker 1: Lyme disease is caused by a tiny bacterium called Borrelia burgdorferi. Under a microscope. Kind of looks like ramen noodles. Borrelia travels on blacklegged ticks, which like to bite rodents and deer and us. Often when a Lyme infected tick bites, you get the famous bull’s eye rash. But not always. Back in 1998, when I was graduating from college and hiking on wooded trails in Massachusetts, I learned to check myself for ticks. Lyme wasn’t that common then? According to the CDC, there were about 17,000 cases that year, mostly in the Northeast. That was also the year the FDA approved limericks.
Speaker 2: It was a vaccine for Lyme disease that was approved by the FDA in 1998. The study suggested that it was about 76% effective. It was only on the market for a few years. And then the manufacturer pulled it off the market because sales basically tanked.
Speaker 1: Now that we’re all armchair epidemiologists, the idea of a vaccine that’s 76% effective sounds great, but Limerick’s never really took off with the public.
Speaker 2: One reason is perhaps that Lyme disease was a lot less common then. Case numbers have increased a lot over the decades. I think the numbers now are about three times what they were in the nineties. Well, so partly there probably wasn’t as much demand then as there is now. Partly it was this sense that that there were some potential side effects that, you know, after the vaccine started being administered, people started complaining about some of the same symptoms that people who have untreated Lyme complain about, like joint pain and arthritis. And it was never proven that that was linked to the vaccine, but it left a bad taste in everyone’s mouth.
Speaker 1: On top of those concerns, a strange phenomenon was taking shape. There was an idea that Lyme was something that only affluent, anxious individuals were concerned about. Maybe because they tended to live in places like Lyme, Connecticut or other New England locations that had a lot of the disease. And it wasn’t just members of the public who felt this way. When the CDC’s Advisory Committee on Immunization Practices, the ACIP, met to discuss the vaccine in 1998, it got a derisive nickname.
Speaker 2: One of the members of the ACIP actually said something like This is a ZAPPIA vaccine, as I’ve ever heard of. And you know, I don’t know why it was viewed as a yuppie vaccine or why Lyme disease would be viewed as a yuppie disease. I think some of it was that. You know, there are other ways to prevent Lyme disease. You can prevent ticks from biting you by tucking your pants into your socks and wearing a bunch of bug spray, that sort of thing. So I guess to some people, maybe a vaccine felt like a little bit like overkill.
Speaker 1: Partly that was because there were simply fewer cases, but also because Lyme and its long term effects weren’t fully understood or seen as a big deal medically.
Speaker 2: The research back then suggested that if you treated Lyme disease, you solved the problem like it was easily treated. That’s still many people’s view today, but I think it’s you know, what we’ve learned over the past several decades is that it’s it’s a little more complicated than that. You know, Lyme disease is sometimes difficult to spot early on. You know, we know a lot more now. And I don’t think it’s as straightforward as we thought it was back in the late nineties, early 2000s.
Speaker 1: Eventually the manufacturer of of lime works pulled the vaccine from the market, citing, you know, poor sales and and limited demand. I wonder what you think that did to the research and development around Lyme vaccines in general?
Speaker 2: Oh, I mean, it had a huge chilling effect on all that research. There was another company who was developing a lime vaccine, and their results from their vaccine came out right around the same time that that Limerick’s published its results. And they just never pursued. They just basically dropped it. And then another. Another vaccine manufacturer was developing a vaccine in, like, the 2013 ish range. They just sort of abandoned that research and never pursued it. And yeah, it just had an enormous chilling effect on the on the entire entire field.
Speaker 1: Now there’s a new line vaccine that might come to market. I wonder if you could walk through why this one might be different from previous attempts.
Speaker 2: Yes. Let me give you a little bit of background on how Limerick’s worked. It was a really interesting and unique mechanism. So basically you get the vaccine and you develop antibodies to a particular protein on the surface of the bacteria called ASP a. So when a tick bites you, it takes in blood from your body. And with that blood is these antibodies to up a and then the the antibodies basically kill the bacterium inside the tick. So you’re never getting the bacteria at all.
Speaker 1: When Limerick’s was on the market, there was a concern among some vaccine recipients that targeting the ASP a protein was what led to side effects like itchiness and arthritis. No research ever linked them. But Cassandra says the new vaccine in development from Pfizer and the French company Valneva avoids the ASP issue entirely.
Speaker 2: They have just removed that particular chunk of Osprey from their vaccine. And then the other main difference is it targets, I think, six different strains of Borelli and not just the one that Lyme Rex was targeting.
Speaker 1: So that it wouldn’t just mean people say in the East Coast, the United States have protection. But but it could be in Germany and in other parts of the U.S. and different places where Lyme is growing.
Speaker 2: Exactly.
Speaker 1: This is in a stage three clinical trial. Pfizer and Valneva recently said they they want to submit their data to regulators by 2025. What do you think it would mean to have a Lyme vaccine on the market in a few years?
Speaker 2: I mean, I think it would be great. This is a big public health problem these days. And, you know, I know a lot of parents are. Parents especially are really worried about sending their kids out into the wild, unprotected, basically from from Lyme disease. And it’s something that a lot of people worry about.
Speaker 1: I think cases of Lyme disease have increased significantly since the era of limerick’s. In 2021, there were about 35,000 confirmed cases, double that of the 1998 caseload. But since so many cases of Lyme go undetected, Cassandra says the real number could be more like 300,000. Obviously, having a conversation about public health and vaccines in this year, you know, as we are still struggling with COVID and with all of the pushback against the COVID vaccines, you know, it really makes me wonder what kind of environment a Lyme vaccine would be moving into. Are there things that make you think that a new Lyme vaccine might have a better path to the market than than the ones did 20 some odd years ago?
Speaker 2: I guess I sort of have mixed feelings. I feel like in some ways Lyme disease is a bigger problem now than it was, which bodes well for for a Lyme vaccine being used. Also, I feel like the anti-vax movement is stronger than it was back then.
Speaker 1: It’s still not clear if the hangover from the limerick saga would make today’s patients more or less likely to want a vaccine.
Speaker 2: So there are a lot of Lyme disease advocates and you would think that they would be on the side of vaccination, but I don’t feel like that’s necessarily the case.
Speaker 1: Tell me more.
Speaker 2: Yes.
Speaker 2: So I don’t know if you’ve heard about chronic Lyme.
Speaker 1: Indeed.
Speaker 2: Yeah. So. So chronic Lyme is sort of a hotly debated issue. And there’s a variety of names that people call it. And researchers, I think, tend to view it as sort of like a coast Lyme infection. Syndrome. And there’s some debate about. What Chronic Lyme is and how it should be treated. And there’s a lot of advocacy that’s that’s built up around chronic Lyme.
Speaker 2: And I think some people in the chronic Lyme community and, you know, it’s not a monolith, they don’t all think the same thing. But I think some people would be skeptical about a new vaccine and worried that the. But the question of the side effects of limericks never got adequately resolved. Like that. There was never a satisfying conclusion into what was going on in those people that were reporting arthritis and other symptoms after vaccination.
Speaker 1: A new Lyme vaccine would obviously be entering into a very different landscape. Is it just that lime has gotten more widespread or is it in more places? I mean, how how has how has that environment changed?
Speaker 2: Yeah. I think part of it is just the spread of the disease out of the East Coast. Part of it is definitely climate change. The ticks are very sensitive to temperature, and there is this thought that they’re going to be able to spread northward as the winters get milder up north. You mean they’re already in sort of, you know, Wisconsin, Minnesota, but sort of North Dakota, northern Minnesota, Canada, that those are places where ticks could become more prevalent and Lyme disease could become prevalent.
Speaker 2: I think part of it is just land use changes. I mean, deer are implicated in all of this because they are a big source of food for ticks. So where there’s a lot of deer, there tend to be a lot of ticks and deer are dependent on land use changes. They like that sort of marginal, you know, forest bordering on open landscape. Yeah. It’s all it’s all a bunch of complex answers about how we use the land and. How the land is changing and how the how the climate is changing and how different species are adapting to that climate change.
Speaker 1: Cassandra Willyard thank you so much for talking with me.
Speaker 2: You’re so welcome. It was a pleasure.
Speaker 1: Cassandra Willyard is a freelance science journalist based in Madison, Wisconsin. And that is it for our show today. What next? TBD is produced by Evan Campbell. Our show is edited by Tori Bosch. Joanne Levine is the executive producer for what next? Alicia montgomery is vice president of Audio for Slate. TBD is part of a larger what next family. And we’re also part of Future Tense, a partnership of Slate, Arizona State University and New America. And if you are a fan of the show, I have a request for you. Become a Slate Plus member. You get to listen to shows ad free.
Speaker 1: So just head on over to Slate.com, slash, what next? Plus to sign up. We’ll be back next week with more episodes. Until then, check yourself for tix. I’m Lizzie O’Leary. Thanks for listening.
