[BONUS] Pollen-food allergy syndrome and stepping on 116 snakes: Tiny Show and Tell Us #13

In this episode of Tiny Show and Tell Us, we cover a study where a researcher stepped on 116 snakes over 40,000 times for science (don’t worry, the ‘steps’ were more like touches, no snakes were harmed in the process). Then we get into why a pollen allergy might trigger an allergy to some of your favorite fruits.

Transcript of this Episode

Sam Jones: Welcome to Tiny Show and Tell Us, the bonus series where you write in with your favorite science news or factoid. We read your email aloud and then dive deeper. I'm Sam Jones and I'm here with my co-host Deboki Chakravarti.

Deboki Chakravarti: Hi, Sam. I'm really excited to do these episodes. They're always so much fun. But before we kick things off today, just a reminder that we are always looking for you to write to us because it makes future episodes possible. So email tinymatters@acs.org or fill out the form linked in the episode description. Okay, let's get into it. So Sam, I'm going to start off today. I have a story from listener Ian. I am going to read it off. A dude stepped on 40,000 snakes to figure out ways to prevent snake bites. So this is from an article called Researcher Steps on Deadly Vipers 40,000 Times to Better Predict Snake Bites. This choice quote is Ian's fave, "The hard part is that after my accident, some people started to see me as reckless. And that is not true. I ran these experiments with a solid scientific base, followed the same protocol thousands of times, and had only one accident."

Ian says like, "Yeah, dude, you stepped on a snake and it bit you. That seems a bit reckless." There are lots of other fun, crazy details to that story covered in the article that Ian linked.

Sam Jones: I'm excited to hear about this because it doesn't scream not reckless to me.

Deboki Chakravarti: Yeah, no, this is absolutely, I guess we can argue about recklessness. But anyway, so this is from a legit researcher. This is not just a guy who was like, I want to see what happens when I step on snakes. So this work was done by a researcher named Joao Miguel Alves Nunes, who is a biologist at the Bhutan Institute in Sao Paulo, Brazil. And he published his team's work in scientific reports in May 2024. He is a biologist, so yeah, I should relate to him. I used to work in biology, but he's a biologist in all the ways that I would absolutely never have been a biologist because truly the idea of stepping on snakes thousands of times is worst nightmare. Actually, I've had nightmares that look like this. So thank you, Ian, for bringing this to my attention. I think this has come up on the podcast before.

I'm someone who thinks snakes are fascinating and would also like them to keep their distance from me. The thing is, despite that fear, I think snakes for the most part also want us to keep our distance from them. Snakes are not out in the world trying to attack humans. They really are usually just responding to the feeling of being threatened. According to the National Institute for Occupational Safety and Health, around 7,000 to 8,000 people are bitten by snakes in the US each year. And apparently it's around five million people worldwide are bitten each year by snakes. But again, they're not trying to really get us. It's usually because someone is stepping on them or purposely trying to handle them, putting themselves or accidentally ending up in a position where they're just like you're in the snake space. And also not all snakes are venomous, and even venomous snakes can do dry bites that don't have any venom in it.

But with all that said, there's still a lot to learn about snake behavior. So even though I myself am never going to be the person to investigate snake behavior like this, there are people who are like Joao Miguel Alves Nunes. And so the study that Ian described to us is focused on a South American viper called the Jararaca, which is apparently one of the most venomous vipers in South America. And what the scientists wanted to know is more about their defensive behavior. So they were around 116 jararaca snakes. They stepped very closely or lightly on them about 30 times each. So that added up to 40,080 total steps. So it was a lot of danger, but it was not 40,000 snakes. And again, I should really emphasize that they were stepping lightly on the snakes. They weren't putting their whole weight onto them or hurting the snake.

And if you're wondering what the protective equipment is for this kind of experiment, Alves Nunes told science that he wore leather boots that were covered in foam, and the foam went around three centimeters above his knees. And so from this work, the scientists were able to figure out some cool details about what makes snakes potentially more aggressive when it comes to biting. So for example, the smaller the snake, the more likely it would be to bite. And also females were more likely to bite. They also found that snakes were more aggressive when it's hotter out. And it also mattered where you step on the snake's body. If you step on the head, you're more likely to get bit than if you step on the body or the tail. And that might all just sound like, great, I found out the snakes are terrifying in more specific details.

But it is actually really helpful, finding out details like this is helpful for figuring out how to distribute antivenom. So for example, if it's warmer out and there are more female snakes in a particular area, you might want to have more antivenom ready in that area. At the same time, the submission, they alluded to a recklessness and accident situation while Alves Nunes was working with rattlesnakes, one was actually able to bite him through his boot. And that was when Alves Nunes learned that he's allergic to both snake toxins and antivenom.

Sam Jones: Oh, no.

Deboki Chakravarti: Right. I just read that and I was like, ah.

Sam Jones: That's so scary.

Deboki Chakravarti: Yeah.

Sam Jones: What did he do?

Deboki Chakravarti: He just went to the hospital, I guess. He's like, "Yeah, I was on medical leave for 15 days."

Sam Jones: Whoa.

Deboki Chakravarti: I would've been on medical leave for the rest of my life. I would never have shown up in the lab again. He was apparently recording this whole encounter with a rattlesnake on a camera, and when he got bitten, he called his mom. And so there's video of him crying to his mom, which is relatable to me of all of this. Again, that is the detail that's relatable because if I got bitten by a rattlesnake immediately I would call my mom. He still continues to do work in this field. I think it did scale back the degree to which he can be involved in the experiments, because finding out that you're allergic to antivenom is not great. If you're wondering what antivenom is, it's actually antibodies that bind to snake venom. And they usually come from animals like horses or sheep. So I think that's pretty neat that there are animals out there that are better able to deal with snake venom, and so we're able to use these antibodies to help people.

But in general, just some safety stuff, don't get in a snake space. I guess if you're a snake person, maybe you will. But a great way to avoid snake bites, just don't get in their space. If you do get bitten, the Mayo Clinic says that you should stay calm and get medical attention. Don't apply a tourniquet or open up the wound or try to suck out the venom. Also, don't try to catch the snake. But a really good thing to do is try to remember its size, its shape, and its color. Even better if you can get a picture so that if you go to a medical provider, they can get the right anti-venom for you.

Sam Jones: That's really smart. Something you wouldn't think about in the moment necessarily. You're just like, I have to get out of here.

Deboki Chakravarti: Yeah, for sure.

Sam Jones: Okay. Yeah, basic safety stuff. Also, we're not here to give medical advice, but don't mess around with a snake bite is really the advice.

Deboki Chakravarti: Yeah, exactly.

Sam Jones: That's really interesting and also makes sense that it was actually not 40,000 snakes total because I was thinking, how do you even make that happen? Having it though, over 100 snakes and stepping over 40,000 times is still wild.

Deboki Chakravarti: Yeah, one snake is enough to freak me out. The idea of just being like, here's 116 of venomous snakes, is a lot to handle. They also had to keep track of details like temperature, the sides of the snake, sex of the snake, where on the snake they're stepping, like on the head, body, tail. There's a lot to remember while you're also dealing with venomous vipers. Science is cool, but there's some science out there that I don't want to do.

Sam Jones: Yeah. There are limits to my interests and thirst for knowledge,

Deboki Chakravarti: Right. But at the same time I have to say, it is good that there are people who want to do this research because it is really valuable information for figuring out how to deal with snake bites and figuring out how to help people who are in my actual nightmare scenario.

Sam Jones: That is actually also a nightmare scenario for me, that I get a snake bite and I'm in the middle of nowhere, and so I can't get access to anti-venom. Like that is so scary to me. Thanks Joao, for your sacrifice.

Deboki Chakravarti: Yeah.

Sam Jones: Okay. So I have a tiny show and tell us from listener Adriana. Adriana wrote in saying, I'm from Brazil, and I recently traveled to Chicago and noticed all the ivies in the city, including the Cub Stadium which is full of them, made my nose feel uncomfortable. I'm allergic to pine. And I learned on a website that there is a cross reaction. So let's talk a little bit about allergic cross reactions in your body. What is actually going on when you have an allergic cross reaction, meaning you're allergic to one thing and then that translates to also being allergic to some other thing? Generally speaking, just thinking about your immune system, when a foreign substance like a virus or bacteria enters your body, your immune system will mount a defense by creating antibodies that target that invader. But for some of us, and I include myself in this because I'm an allergy person-

Deboki Chakravarti: You're calling yourself out.

Sam Jones: So for some of us, the immune system creates antibodies that recognize something totally harmless like pollen or tree nuts. Like how many people are allergic to tree nuts? Or pet dander, I'm allergic to cats. So my immune system seems to do this some as well. So your immune system recognizes that as a threat when it's really not. So when we then encounter these allergens in the future, our antibodies will tell our immune system your body is under attack. And so then that causes symptoms like a runny nose, sneezing, itchiness, fatigue. And then in some severe cases, someone might actually experience difficulty breathing, which fortunately I don't have, but that's really scary thinking about swelling, rash, anaphylaxis.

So Adriana mentioned hearing that there was a cross reaction between ivies and pine. Allergic cross reactivity occurs when you have proteins from one thing that are really structurally similar to an existing allergen. The person's antibodies are going to bind to that substance and their immune system will mount the same defense. In Adriana's case, she's allergic to pine, and for some reason her immune system seems to be recognizing some type of ivy the same way it recognizes pine, and so then she's having this allergic response. It was hard to find anything specific about pine and ivy cross reactions. There are so many different kinds of pine. There are also so many different kinds of ivy. But apparently English ivy is a really well-known common ivy, and it is also really well known for being an ivy that causes people to have an allergic reaction.

Deboki Chakravarti: Oh, no.

Sam Jones: And also English ivy isn't actually native to here it's an invasive species, but it's here. When I got this email, it made me think of something that I've been talking about with my husband actually, because there are a lot of different cross reactivities out there. And there are many too different types of pollen and fruits. My husband developed an apple allergy after we moved to the DC area, likely because of the pollen here. So some of the pollens here, I guess really closely resemble some of the compounds that are in apples and pears and plums. And so his mouth gets super itchy now, and this never used to happen. And so I guess there's this whole syndrome known as pollen food allergy syndrome, which is unfortunately PFAS, which is now really misleading. But also it's sometimes referred to as oral allergy syndrome or OAS. And so it occurs when someone's pollen allergy leads to a new allergy to certain foods. So I'm pretty sure that's what happened.

Deboki Chakravarti: So is it pollen in particular that often drives this?

Sam Jones: Yes. So you move to a new place, there's some tree producing some pollen that you're allergic to and then all of a sudden you're like, I can't eat this apple, or I can't eat this other food, which is such a bummer. So I guess up to 60% of adults with pollen allergies may experience this syndrome, which is a huge percentage. And so for this episode, journalist Ariana Remmel actually did the research and came across a website that had a whole table labeled cross-reactivity allergy list. And it seems like sensitivity to birch pollen seems to elicit cross-reactions from a ton of foods compared to others. So apparently, I don't know, there's something about the birch pollen. But some of those are kiwi, bananas, celery, and a bunch of other stuff, which I'd be so sad if I couldn't eat kiwi or bananas.

I'd be so sad. And another one that I thought was fascinating was latex fruit syndrome, which causes people with a latex allergy to develop sensitivities to fruits also like bananas, avocados, kiwis, and chestnuts. And with all of our episodes we have on the page where the transcript is, at the bottom we have references. I'll make sure that all of these links are listed so you can go and check out these tables for yourself. But it's really fascinating and it's super widespread. So thank you, Adriana, for writing in because this opened up this whole world of allergic cross-reactivities that I didn't know about.

Deboki Chakravarti: Yeah. I had no idea that so much of it could be related or correlated to pollen allergies in particular. That's crazy to me. In my head, it makes sense. I don't know if I'm constructing a logic around it where I'm like, well, pollen is the thing in the trees. And it helps them reproduce, and so it's everywhere and somehow that's going to resemble fruits, somehow it makes sense. But it also seems so weird, and especially latex.

Sam Jones: Yeah. It made me think a lot more about what is latex actually made of? What are the compounds in that that looks similar to the ones that are in the fruit that we eat?

Deboki Chakravarti: Is there something about kiwi too in particular? Because this comes up with both the birch pollen and the latex.

Sam Jones: There are definitely some fruits that are much more commonly going to have that cross-reactivity, and I really wonder what it is. So there's foods that are listed to avoid if you have a latex allergy, but then there's also ones that are like, oh, this is low or undetermined. We've got coconut, cucumber, chickpeas, cherries, apricots. It's a huge list.

Deboki Chakravarti: Yeah.

Sam Jones: Lychee, great. Love Lychee. But yeah, the ones that have a potential cross-reactivity, it's like avocados, bananas, chestnuts, and kiwi are listed under high latex proteins. And then moderate latex proteins are like apples, carrots, celery, melons, papaya, potato, tomato. It's fascinating. I could look at these charts all day and be like, hmm, because there are certain things I eat where I'm like, oh, my tongue feels a little swollen. I'm like, I wonder if that's a little bit of a cross-reactivity that's fortunately not too strong, and hopefully it doesn't grow but we'll see.

Deboki Chakravarti: Yeah. One of the things that right now we're trying to figure out, my baby has eczema and the doctor's like, oh, you can try eliminating dairy and then also try eliminating soy to see if that clears it up at all. I don't really have dairy that much because my husband's vegan, and so we don't really have much dairy in the house to begin with. So that didn't really seem responsible. But right now I'm working on eliminating soy, which is much harder, especially when you are with a vegan person because a lot of our protein…

Sam Jones: A lot of stuff is soy.

Deboki Chakravarti: ...in the house is soy. But I think there is also a cross allergy there as well. I'm not sure though.

Sam Jones: Yeah, I think so. I was also like a baby that had eczema. And also the same thing with my mom was like, you got to get rid of dairy. And I don't think they mentioned soy at the time. Maybe they just didn't know.

Deboki Chakravarti: Yeah, I think also, I remember our doctor saying that it's not clear if the soy protein gets into breast milk as much as dairy does, as the cow's milk protein does.

Sam Jones: Allergies are really, really weird and fascinating, and a reminder that our immune system is very smart. But sometimes not so smart because it's identifying stuff that is definitely not harmful and making you react to it.

Deboki Chakravarti: Yeah. Thanks, Ian and Adriana for submitting and thanks for tuning into Tiny Show and Tell Us, a bonus episode from Tiny Matters, created by the American Chemical Society and produced by Multitude. And a big thank you to science journalist Ariana Remmel who did the research for this episode.

Sam Jones: Send us an email to be featured in a future Tiny Show and Tell Us episode tinymatters@acs.org, or fill out the form linked in the episode description. We'll see you next time.

References:

[BONUS] Pollen-food allergy syndrome and stepping on 116 snakes: Tiny Show and Tell Us #13

Transcript of this Episode

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