Leader of the Pack

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When I think of the great majestic predators in North America, I think about wolves and cougars. But what if I told you that those predators are susceptible to some of the same parasites that infect the orange tabby currently sleeping on your laptop and demanding fancy feast or Meow Mix or whatever it is this week? You guessed it, we're talking about Toxoplasma gondii.

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A the parasite that keeps pregnant women from changing litter boxes. But here's the kicker. A recent study found evidence that this parasite may increase the odds of an infected wolf becoming pack leader.

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Crazy, right? We have a really interesting story coming up next, so stay tuned.

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Welcome to the infectious Science Podcast.

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This is not just another Science Podcast Nope. Infectious science is produced by a team from the University of Texas Medical Branch and the Galveston national lab where we study some of the most dangerous viruses on the planet.

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Our goal is to inspire future scientists towards a career in science with a focus on one health, one health one planet. That's right.

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One of the approaches public health threats by examining the connections between people, plants, animals and the environment. We all share this show we'll explore how one health is your health. So sit back and learn something infectious science where enthusiasm for science is contagious. Hello, listener. Hi, everyone. Welcome back to another episode of infectious science podcast here and UTMB, the galvus National Lab. I'm seated here with my friends and colleagues, Dr. Daniel Sweetnam, Dr. Dennis benta, and Matt Dasho. And we're doing something a little different today. And we need to know if it works. So if you like what we're doing today, we want you to tell us in the show notes, leave a comment, hit the like button, whatever it is, give us a follow tell a friend.

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And we're going to link to this paper in the show notes. What we're doing today is we're talking about a paper, a little bit of a journal club.

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Yeah, journal club.

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And we're all going to talk about this paper. Danielle, you brought this paper, it was so cool to read. I've never read about this topic before. So it was really interesting for me to delve into it. Tell us what this paper is.

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So this paper is a really exciting paper and it was blowing up all over science Twitter a few months ago when it came out. And it was published in Nature, which is a really high impact journal Nature Communications. And it's about a parasite that you may have heard of, it's texel plasm, gone di and this parasite. They're looking at it in cougars and wolves and discovering that it might be altering the behavior of wolves. And even altering pack dynamics. Even if the parasite infects just a single Wolf, it can change that dynamics of the entire pack. And I just think that's so exciting that something so small can have such an incredible impact. And that's kind of to me, just like the epitome of why microbiology is so cool.

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Yeah, this is super cool. So I did see this paper on Twitter as well. But why did you really like picot? And and like, what captured your interest? And why did you select this paper?

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Well, most of what we know about Toxoplasma gondii. I think most of it we know about in prey predator dynamics, and we'll talk about that a little bit later. And Yellowstone National Park is this really interesting area. And that's where the study is being done, where wolves and cougars, their territory is kind of overlapping. And so we have this really exciting multi predator multi carnivores system that we don't normally see that wolves and cougars are usually, even though they have the same prey are usually kind of selecting to be separate. So this really interesting area is allowing for this interesting spillover of a pathogen, which I just think is just this really interesting area and I will kind of want to go to Yellowstone National Park. So it's a nice place to think about.

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Yeah, I've never been either. So listener if you're interested in sponsoring a an infectious science trip out to Yellowstone, we know take Venmo Cash App, Zell. So Dennis, you're the vet tell us about toxic so I only know about it and humans, right, we learn about and I've taken care of folks who've been infected with toxo mostly immunocompromised people, people with HIV AIDS usually advanced, the HIV they're immunosuppressed. They have low immune systems, they can't fight off viruses and bacteria like someone who's got all of their white cells and then we also hear about it in pregnancy. You know, those don't clean the cat box, you know if you're pregnant, because you may aerosolized the feces and inhaled it or be exposed to it.

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What is this pathogen and what does it look like in animals?

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You know, in vet school, you've Toxoplasma gondii is obviously a staple that you have to learn about, but not so much because it causes you know, devastating disease and animals but obviously, because it's a zoonotic disease and can be transmitted to humans, but we do learn about it. Obviously, cats being the main host and know a lot of Veterinary Medicine.

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focuses on domestic animals on cats and dogs. But it's not just house cats, right? No, that's That's correct. Toxoplasmosis is a disease cause you know, as we talked Toxoplasma gondii i and it theoretically can infect any or many warm blooded animals, including pets, livestock birds, and obviously people so I think the reason why we focus on cat so much domestic cats is because they live in close close proximity to us and a big one health question humans and pets and close proximity and, and human infection can occur through domestic cats. And I think that's why this is part of the education and why we learn about this so much. And, you know, typically most infected adult cats, they appear healthy.

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However, some cats may develop pneumonia, liver damage or some other health problems, but in most of the time, it's really avert, there's no signs of illness in cats, maybe if they are infected, they are lethargic, loss of appetite, but it's not really just a big deal in vets medicine.

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So some people are some people from cats being people, cat owners. So some cats, that mean do they manage? Some of them don't have any symptoms at all right? I mean, they can most of them. Yeah, most of them. And if you have an immunocompromised cat or a kitten, for example, feline HIV, right F IV that can immunosuppressed, the cat, then the parasitic infection has no control or is not controlled, and then we'll just go rampid in the cat and then the cat will get sick.

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Okay, so I'm hearing why it's important for cats certainly know why it's important for humans. So Daniel, when you were reading this stuff, what prompted these guys to do this study, what was the main problem they were trying to understand.

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So let's back up a minute, because there's a couple of things I really want to emphasize. Okay, emphasize emphasize this, this is a protozoan, just a single cellular parasite. And like Dennis said, It infects warm blooded animals in general, the real big important key here is it needs some type of feline to replicate. This is really, really critical part of its lifecycle, the direct host is some kind of Feline, everything else is like an intermediate host. And when it spread from an animal that's not a cat, it escapes the intestinal lining, and it can form me cysts, and muscle and brain tissue. And there's a lot of evidence that it could affect behavior. Now, the way it's spread is by basically three ways you can be spread by consuming the parasite eggs, but that can only come from one of the cats, and it can be through eating the cat, or it can be through coming in contact with feces of the cat or the scat or something that's been contaminated with it. The other way you can contract it is if you eat infected meat, anything that's been infected with the parasite. So it can be an infected cat or an infected dog or cow or anything like that.

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But the really important thing that you have to remember for the rest of the story is it's only replicating in cats, or cougars and our story. And so you use a couple terms there. I just want to like clarify. So you said direct host and an intermediate host right? So can you kind of flesh those out a little bit? Because I in my head, I was actually reversing them. I was like, Oh, the intermediate host must be the one where it's replicating. And then the direct one is where it's reversed, right? Yeah. So the direct host is where it's replicating. And that's cats. Everything else is an intermediate host, you can get it from eating the intermediate host. But you're not going to get it from coming into contact with the feces of the host.

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So are you saying in the intermediate host says no replication in the none at all, no. amplification of the parasite in the intestine?

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No, it just kind of travels from the intestine to kind of muscle or brain tissue and forms assists to protect itself and it goes chronic, it kind of just hangs out and doesn't do anything unless you're immunocompromised. And then it can start to cause some kind of inflammation in some disease, but it will just hang out forever indefinitely, but not replicate.

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And I'm against scare tactics.

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I'm against just anybody knows me. I don't like people would be scared. But the numbers that we're seeing were pretty crazy.

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Like 2 billion people in the world. Probably infected. Yeah.

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Okay. That's a lot a lot. Right.

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I don't know the exact number. But it's a very high prevalence in the population, which is something we don't always think about. Right?

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Yeah, well, probably because it's not causing any disease in most of those people. And in most of those animals that's not causing any disease. Yeah, I think this is something that the major take home messages I would say is that a lot of people get exposed to toxoplasma and they will deal with the infection, but they will just seclude the parasite and there's no clinical signs as no threat to help in any way. So that's the most common outcome of an infection or an exposure with toxoplasma.

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I think that's kind of like really something we need to emphasize.

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Yeah. Okay. So that's kind of The basics of the parasite. But what's really, really cool is this kind of idea that this little micro unicellular organism is there's a lot of evidence that it can change behavior, even in these hosts where it's not doing anything else, and it's just hanging out.

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So, for example, in rodents, and monkeys, and hyenas, it all really makes them more prone to do risky things. In rodents, it makes rodents less adverse to house cat urine, and in monkeys that makes them less averse to leopard urine. And in hyenas specifically, it makes them a lot more bold around lions, right? These are all really dangerous things, this increases the likelihood that these animals that are infected are going to be around a wild cat that can eat them, and then that cat would become infected. So this parasite makes the animals bolder, these prey animals Boulder, puts them at risk, and put some around these cat predators and then kind of perpetuates itself. And that kind of interesting kind of subversive style almost sounds a little bit like rabies, right? Like where you have herbivores that all of a sudden become more docile when they infect an easier prey for predators. Correct. Do you would you agree? Yeah, for sure.

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Yeah, it was so interesting, Danielle, because you sent me down a rabbit hole when you sent this paper because I started thinking, oh, man, like, I only know the clinical part right out, I know, the dose of antibiotic you're supposed to give I know when you're supposed to, you know, the guidelines for HIV say you're supposed to screen for talkshoe. And when you're supposed to treat and so I know those things, but I didn't know anything else about what toxic do to behavior. And as I started traveling down the rabbit hole, into the literature, I found several papers, right in humans describing that actually toxoplasma infection is associated with things like schizophrenia, there was a paper that described that people who consume alcohol were more likely to have behavioral effects, if they were toxic positive, found one paper that was done on university campuses, it was kind of a funky study design, but they looked at college students and found that people who were business majors were 1.4 times more likely to be toxo IgG.

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Positive. So.

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So compared to what biology majors, right.

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So I don't know what that says about all of us. I was a music major. So now I think all these papers are really interesting. And I think this has been a theme for a long time, what toxoplasma can do to behavioral changes. And it's not a new theme, right? I mean, this we know this from the animal kingdom, how parasites can modify, and behavior and so on.

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I'm still skeptical, though, what is the likelihood of 1.4 times really mean?

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Right, the paper I saw is that it looks like people that have a chronic infection with toxo have increased testosterone and dopamine. So there's an idea that maybe with the increase of those two hormones that that might lead to risky behavior.

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But what does risky behavior look like? There's a lot of types of risky behavior. So it might be something that's just if there's a behavioral change going on in the human population, it might be really hard to quantify, because risky is super subjective, right. And it's easy. When we talk about the paper they define for risky behaviors that they're going to look at. Yeah, but I think also more like the biostatistics like 1.4% times more likely, is this very high, or it's just hard to do prospective studies. We can't like infect people intentionally.

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In fact, freshmen, and then see what major letters from iOS x community, yeah, on this, we're not suggesting this, please don't do that. But it was interesting to me to see that there were these at least correlative studies in the human literature saying, well, actually suicidal behavior, schizophrenia, which is heavily dependent on dopamine. So these were altered by the presence of this parasite, or at least have antibodies to this parasite. And so very, very, very interesting that it could potentially have some nose to humans. Maybe in a few years, when we talk about mental health, we'll be looking at infectious diseases a little bit more closely and associated with that, but yeah, I know a lot of infectious disease doctors that would be very pleased to know they they've their their field is so much so relevant in so many ways. Yeah. Infectious disease and cancer, infectious disease and hypertension, infectious diseases and heart disease, you know, infectious disease and mental health. We know from COVID-19 that people who are dealing with post acute COVID syndrome or long COVID are dealing with a lot of mental health side effects. Right.

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So what happened in the paper?

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Let's talk about the paper sorry, tangent go over. Okay.

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So we talked about all these other studies where toxin has been studied, and I mentioned before, most of the studies, at least in the animal kingdom, were looking at predator prey dynamics, but that leaves a lot of other kind of directions up for questions. And in the Yellowstone National Park wolves were driven out of that area in the early 1900s. And then were reintroduced in 1995, like between 1995 and 1997. And since that time, there has been a ton of effort to monitor their health and behavior and something really similar happened with cougars, although the the Cougars reintroduce themselves, but still, there's been a lot of monitoring Cougars are gonna go where they're gonna go. In this case, don't try to tell a cougar. He or she can go I don't know why that's funny. I feel like something about it is funny. Okay, so yeah, these animals that were excluded from this area and reintroduced Wilson Cougars both prey on smaller animals, but they're rarely found in the same location, except for here at Yellowstone National Park specifically in the north. Most of the Cougars kind of colonized the the northern part of the park where there's lower elevation. But in the winter, the bison and elk and mule deer migrate down elevation into this northern part of the park. And when the prey animals migrate, well, the wolves follow. So for this period of time in the winter, there's this really solid overlap between the two.

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And the Cougars just so happened to be carriers of toxo, specifically, and it's actually increasing quite a bit between 1989 and 2004. About 45% of the Cougars in that area that were surveyed were toxic, positive.

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And more recently, a survey that was done in 2016 to 2020, that number increased to 73% of the Cougars in this area are toxic positive. So boom, here's this really great opportunity, the samples that have been collected. There's data about behavior, there's data, there's samples, serology samples that have been collected, this is a great area to really leverage 26 years worth of data and samples that were collected to look at this interaction.

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So Daniel, when you say a toxic positive, so in technically term, in technical terms, they are seropositive, they have antibodies against Yeah, Toxoplasma gondii. I do you know, is the the sero positivity automatically a sign that the infection has taken a foothold in the person or the animal?

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Well, I think it's assumed that evidence of prior infection indicates current infection, because I think what's known about toxo in general is we don't clear the infection, the virus creates cysts in the brain and the muscle tissue and persists for the lifetime of the animal. I haven't read anything about if there are any animals that are able to clear the infection. So I think if you've ever been infected, it's assumed, at least in this study, and other studies I've looked at the infection is still there.

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Right? So that makes sense. But can we infer that only because it's positive that there's some behavioral change automatically?

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No. But that's what they look at. So they had two goals.

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First, they want to determine because not all the wolves in the park were living overlapping with cougars. So they were saying what kind of factors contribute to infection and wolves. And the second thing they're trying to look for is does infection alter wolf behavior? So there were two goals?

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That was really, really cool.

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And so gosh, I can't imagine how they did that. Did you get a sense of like how they fancy math behavior? Yeah, it's really was a lot of math. Yeah. A lot of math in there.

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Yeah. So for the first kind of question to determine the factors that affected the likelihood that the wolves would become infected with toxo. You can't just say, were they living in the same area, right, because there's a lot of other things that can contribute. So age of the wolf sex of the wolf, whether or not the wolf was a pack leader or not the coat color of the wolf, things like that. And then what poor portion of their territory was overlapping with the Cougars. So men kind of accounted for that using a variety of like statistical tools and mathematical modeling. And what they found for that question was that the only feature they found that was significant was whether or not the wolves shared territory with the Cougars. And the the wolves that had a lot of their territory like high overlap with the Cougars were nine times higher odds of being infected with toxo.

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So we this basically showed these these environmental changes happen, the wolves migrate down to share kind of the same habitat as the Cougars do. And because of this overlap, we definitely see an increase in transmission from the direct host to this intermediate host where the thing kind of find its end pathway.

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Talking about transmission. You know, I think all of the listeners who own dogs know how dogs sometimes even pick up cat poo, right? I think we've we've all seen this. One fun fact that I found doing my research on this is that the the O says from Toxoplasma gondii I they actually need to spend 24 hours, maybe even up to five days depending on environment. mental conditions in the environment before they can become infectious. So it's not that you find feline stool or something like that, and then it's immediately infectious. So it takes some time for the the old cysts to mature for lack of a better term to become infectious. So I know this is not really covered in this article, but so it can't be the fresh stuff.

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Fresh juicy stuff. It's gotta be the rock hard, you know, been out there for a little while.

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Those are that's the real is so to say so full anything about seasonality in this paper?

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And do you think they speculate they say that they don't think it is infected prey?

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So they don't think it's the infected elk or deer? And they did some surveillance? And I think elk it was and they didn't really find any seropositive.

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Elk are a very small portion of seropositive elk. So they suspect that it's direct contact with the Cougars, or the Oh sites in the scat, I guess. But in the winter, I don't know maybe there's like a freeze thaw thing going on, or could even be contaminated water, or contaminated vegetation or something. Or I mean, they could even be eating a burger. I don't really understand those dynamics, like do wolves. Would a pack of wolves prey on a cougar? Or would that be the other way round? It'll get emboldened. Yeah. Maybe because if a wolf were to eat a cougar, or they came across a dead cougar or something, and Dennis the wolves do that, you know? Sure. Yeah. I'm just amazed by the seropositivity level of what was it? 45% or something like that. So there must be ongoing transmission within the Cougars? Well, yeah.

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And also to spill over to the dogs. Dogs to the wolves. So sorry. Well, so what else did they find? So that was their first study?

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That was their first question.

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age, sex, social status and coat color did not affect transmission of toxic to wolves, but overlapping territory did.

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The second question was the big one that kind of cool one did toxic infection alter wolf behavior? So here were they identified four risky behaviors.

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The first one was becoming PAC leader. They consider that a risky behavior because there's some kind of violence involved in that, as I understand it's quite a violent transition like a fight. Is it like a fight to the death? Or is it or somebody retreat or somebody? Yeah. So you would expect that to be that's obviously a risky behavior.

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I mean, going into any kind of leadership politics, this is risky behavior. You know, you're putting a lot of the comfort of your home anonymity. You know, these wolves are just putting themselves out there.

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Yeah, maybe that should be a study. Yeah. Parasites among political leaders? Oh, gosh, don't get us started on that.

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There's so many jokes there.

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There's like you can take it down.

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Yeah, okay, let's remain focused, bringing in the second risky behavior was dispersal. So basically, this is when a wolf leaves his pack or her pack and never comes back. And usually this is, this is really risky, right, because you lose the protection of the pack, particularly in the harsh environment of winter. But generally wolves do this, and it increases the likelihood that they'll find a mate. Or maybe they can come across another pack and try to challenge that pack for leadership. So dispersal is another high risk behavior in wolves. And then the other two were related to people. One was habituation, which is how likely the wolf is to approach people or a vehicle.

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And then the the final risky behavior was Did they die as the result of interaction with a human. So those were the four risky behaviors that they assessed. So first off, they found that of the wolves that dispersed, they were 11 times more likely to be infected with toxo. So that's a pretty big increase, and your willingness to disperse. That's pretty incredible. And this is kind of really the thing that stuck out the odds of an infected wolf becoming a pack leader was 46 times higher in a seropositive infected wolf than an uninfected Wolf. So that's almost 50% Higher. So that's huge. And just imagine you've become leader of the pack. And now you're the one taking risky behavior, and you're maybe engaging your whole path in this new risky behavior.

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And just think of the implications for like social learning and new kind of wolf cubs that are being born into that pack. That's a riskier pack. But the two things about humans are the two risky things about humans, they didn't find any statistically significant data. So that is good. And it's not increasing the likelihood that the wolves are going to be approaching people or something like that, because that's quite risky for them, right? Like that's, yeah, people are probably scared of that.

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We're scared of wolves, but it's probably the biggest risk to them.

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Right? The thing is, is they even acknowledge it that their sample size for that was very, very small. They didn't really detect much interaction between wolves and people. So wolves that are infected might be more likely to approach people but I'm really just a thought here on the side. Not crucial, but I think that's when it comes to rabies education.

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And we always teach people that if you find a carnivore or omnivore that's very docile that this could be a sign of, you know, some form of infection or rabies infection. Right. So a wolf approaching being way more comfortable with the human could trigger somebody you think, you know, we need to shoot the wolf because it's you know, has rabies.

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Interesting. Yeah. No, that's, that's fascinating. Danielle, as I was reading that I was just, again, harkening back to that human side thing, we're definitely see differences in behavior that's caused by this particular parasite. So very cool. Yeah, it's so cool. It's so fascinating.

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What do you think are the implications for this? They've done this really elegant study, they've really, I think, shown something. And certainly that has been shown experimentally in controlled conditions, in rats, and as you mentioned, in some other animals, that there are these behavior changes that happen with Toxoplasma gondii, infection. And now they've shown in a real world environment, and with control of a lot of variables and a lot of data, that this is independent of other things. This is a contributor to not only changes in the individual's behavior, the individual wolves, but the pack behavior, like you pointed out. So where do you think this leads us? What are the implications for this? Where does it go for maybe other diseases? I always think, you know, one, health is not always about human health, right? It's about interconnections human animal environmental health. And so we selfishly sometimes look at animal studies as like, some excuse to apply it to human populations, right? Do you think we're there yet to be able to extrapolate that? Or is it just another line of investigation?

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So I don't know, maybe it'd be better to ask you those questions as a physician, because for me, what I'm thinking about is how does this affect park management? How does this affect wildlife management, the overlap in these two predators is kind of something that isn't really seen anywhere else. And it's seen in this area where the wolves were artificially reintroduced into that, and something that we looked more closely at and maybe should look more closely at moving forward. And the impact that this could ultimately have on the wolf population, right?

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This is all happening during the winter. And this is also just so happens to be when wolf mating season and whopping season is going on, this is increasing the likelihood that a wolf will become infected while they are pregnant and carrying cubs. And this is going to increase the likelihood that it's transmitted vertically from mother to offspring. And if just like within humans, there can be really extreme damage to the fetal Wolf, if the mother is infected. So will this have a long term decrease in the wolf population overall? Will it increase the likelihood that the wolves will die? Because they're taking a risky behavior? Does this kind of interaction with Cougars put them at risk in other ways than just kind of the predator predator carnivore, carnivore interactions? So yeah, that's really what I'm interested in, and what I'm going to be looking for in the future.

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Well, if the authors are listening, please continue to collect data for the next 26 years.

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And what an amazing example of why it's so important to collect data for long periods of time, right? The study has 26 years worth of data. Oh, my gosh, it's incredible. How, how old were we 26 years ago? You know, obviously, the people that did this work, were not the people who started it. So what kind of foresight went into this?

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Absolutely. I think this is a very elegant study. I think it's just amazing paper. I feel like I'm the Debbie downer here, the critical voice. But one thing that I just have a really hard time wrapping my head around is how does assist really leads to behavioral changes. I mean, you talked about different levels of dopamine, different levels of testosterone. And I think that makes a lot of sense. But from what I remember from histopathology, back in the day, those parasites those cysts, they randomly occur in the brain, and not in specific regions of the brain. What you would expect if you think about the hypothalamic, pituitary gonadal axis, or whatever it's called, right? So where you have to have a lesion in the hypothalamus, and that will maybe change the expression of GN HR or something like that, right. And last, but you know, like the axis that triggers testosterone production, so I just don't understand how a randomly placed cyst will lead to an increase in testosterone.

00:29:43.650 --> 00:29:57.990
And that's, I think, for endocrinologist answer and there's probably a couple of experimental papers that describe that. We do know that a lot of infections either by way of a direct effect of the pathogen the infection happens.

00:29:58.200 --> 00:30:26.730
Thing sets up shop, it can cause the secretion it can induce by secreting its own chemicals that can cause the secretion of certain hormones, or neurotransmitters like dopamine, but also possibly the inflammatory response. Right? So maybe it's a question of how our bodies are responding to the pathogen. So it's that connection. And I can't speak intelligently about either of those two things. But I would say those are interesting questions that for me would come from this.

00:30:26.730 --> 00:30:59.190
Absolutely. And I think that we always have these discussions in the one health realm that's when it comes to one health, we talk about policy and have these frameworks and but I think what's often missing missing is one health research. And I think this is such a good example of One Health Research, where you have the behavioral changes. And now let's dive into the molecular side of things. Let's now understand the pathogenesis behind this. And I think that is, by definition, one health research, and I think there needs to be more effort on this.

00:30:59.459 --> 00:31:39.298
I think that would be maybe the next paper we can read, we'll go look and see if any of our listeners know of any papers that talk more mechanistically about how parasites or viruses can alter expression of hormones or neurotransmitters. Yeah, I'm sure there's people I'm sure this is an area of research, not my area of environmental peace. You know, I used to live in Botswana, Southern Africa. And there's this lovely Game Reserve, right across the border from Botswana into South Africa. That's called the Monday QA game game reserve, and shout out to Tao lodge where we usually stay and bow in the local language means means lion.

00:31:39.778 --> 00:32:49.559
So this particular region of the park that we stay in is full of lions, and in fact, becoming quite a big problem in the park, because not only are they very territorial and battling each other, but they also compete for food sources. And over the years, South Africa, instituted a lot of safety policies for wild animals. And so they've also become a destination for rescue lions. And so as the lion population has, in some ways, naturally, and in some ways artificially increased in this enclosed game park, but it's still a game park, I wonder about, you know, these are feline animals, right? So how much toxo is out there? And what are we gonna be seeing maybe very bold giraffes, oh, that are just coming up to two lions, two lions and saying, Hey, Scott, maybe they're herbivores, but you know, that can cover the plant life. And so I, you know, you really do wonder about not only natural increases in these populations that can be replicated hosts for these pathogens, but also the dynamics of when humans introduce them.

00:32:45.630 --> 00:32:51.960
So human behavior, once again, it's not always terrible. We're doing something good, right?

00:32:51.960 --> 00:32:57.390
We're trying to save lions, right. But there's always potentially downstream consequences to be considered.

00:32:57.660 --> 00:33:13.230
So Matt, for our listeners that don't know too much about toxoplasma. What can you tell us about congenital toxoplasma infection and pregnant women and cleaning the litter box and so on? Do you have some advice? And can you tell the listeners a little bit about that?

00:33:13.470 --> 00:33:28.650
So I can't say much intelligently because I'm not an OBGYN. Boy, the last time I took care of a pregnant person was a long time ago. But generally, what we know is that it causes congenital fetal malformations.

00:33:23.519 --> 00:33:33.210
It's one of the torch infections that is associated with fetal abnormality, what is what is torched mean?

00:33:33.720 --> 00:34:26.039
So thanks for asking that Dennis. Torch infections are toxoplasma others which includes syphilis, and hepatitis B, rubella, cytomegalovirus, CMV, and herpes simplex. So that's a group of infections that we're always keen to prevent, in practice, how do the babies become its vertical, so these pathogens are able to traverse the placenta. So as you're just stating, as your fetus is growing inside the uterus, there's this really beautiful apparatus, that's the placenta that it's not much to look at when it's on the outside on the inside. It is just a glorious network of blood vessels and signaling and it's basically the main organ that filters maternal blood for any kind of adverse things and make sure that whatever is coming to the fetus is going to be nutritious, and there are certain pathogens that evade that placental barrier.

00:34:26.248 --> 00:35:20.670
So Danielle, what would you say if a pregnant woman wants to surrender her cat because she's afraid that she could get toxoplasma have your husband take care of the cat. So the primary risk to pregnant women would be in dealing with the cat excrement and cat feces, so cleaning the litter box or if you have an outdoor cat and you're gardening or something like that, or if you're living around a lot of stray cats so there's certain ways that you can protect yourself from that kind of transmission. You can wear gloves while you're changing the litter box, you can ask someone else in your family To change the litter box, you can have your cat, go stay with a friend during the time that you're pregnant and then come back and live with you. So there's definitely ways that you can keep your cat in your life after you're pregnant, and be safe and confident that you're not going to get tuck. So yeah, and it's not like a guarantee, right? It's a risk.

00:35:20.670 --> 00:35:57.539
It's like anything your cat might not have toxo. And so I think, you know, you don't want to cause this widespread panic that you know, every time you get near a litter box, you're gonna be at the risk of getting toxo I think it's just important to know, these are risks that if you have the ability to have someone else, change the litter box, great. If not wear barrier protection, wear masks, just be safe about it. We tell pregnant women not to eat unpasteurized raw cheese, right for risk of listeria infection. We will talk about safe sex, we talked about a lot of things to try to prevent potential diseases that could harm the fetus. So I think it's just one of many, but it doesn't mean that get rid of the cat is probably overkill.

00:35:57.840 --> 00:36:01.980
And you can still go visit Yellowstone National Park if you're pregnant.

00:36:02.340 --> 00:36:09.329
Absolutely. Just stay maybe, you know, just go away from the calcified feces of the Cougars.

00:36:05.130 --> 00:36:11.670
Right? Those are those are not, those are the next.

00:36:12.599 --> 00:36:55.860
One thing I also wanted to point out when it comes to the potential risk of pregnant women acquiring the infection from cats. Cats don't shed toxoplasma consistently, they will only shed the old cysts or the eggs in their feces for approximately 10 days after the initial exposure. Oh, interesting. So it's not that a cat you own a cat in its lifetime, it will just shed Oh, is this or eggs, toxoplasmosis. It's just up to 10 days after the initial exposure. So the question is, you probably don't know if your cat has been exposed and when and will be exposed. But that's definitely not the concept of lifelong shedding.

00:36:56.159 --> 00:36:57.780
Interesting, interesting.

00:36:57.900 --> 00:37:20.909
And if what you said before is true, Dennis, which is that it takes some time in the environment for toxo to develop the ability to infect a new host, then I mean, as long as you're cleaning up fresh stuff, then changing the litter pretty frequently. Shouldn't that be pretty good? That'd be a pretty good practice, I would say. So it's just can't be old rock hard stuff, right?

00:37:21.119 --> 00:37:35.639
Yeah. And if you have an indoor cats, and you know that the cat is not going outside eating rodents that are infected, or something like that you at least have a grasp on if your cat will acquire or has acquired the infection. Does that make sense?

00:37:35.639 --> 00:37:36.360
Yeah, for sure.

00:37:36.599 --> 00:38:06.150
I have feral cats that live in my backyard. Galveston has a lot of feral cats. But to the point where we always want to advocate for especially people in our area, too. If you have feral cats living in your area, you can call the Humane Society to help with the trap neuter release program where they'll, they'll take the cats and they'll neuter them or spay them to help control the cat population. Because certainly as we see more and more cats, we're potentially going to see one over awesomes can can acquire toxoplasmosis. Gotta get Lucas on the show, buddy?

00:38:06.179 --> 00:38:16.500
Well, it would be they would be indirect hosts. Right? Because they're warm blooded, but they're not feeling so it would be an indirect house, they can acquire infection, but they wouldn't the parasite wouldn't reproduce.

00:38:16.800 --> 00:38:19.019
That makes sense through Danielle, any closing thoughts?

00:38:19.019 --> 00:38:22.199
Final thoughts about the paper?

00:38:19.019 --> 00:38:40.769
Anything else you want to say about it? Yeah, so I just really thought this was the coolest paper ever. And I hope we get to do more little journal clubs. So please, please, please let us know. If you like this kind of style of podcasts, we would love to hear from you. And if you come across any papers or topics that you think are interesting, let us know in the comments or shoot us a message.

00:38:40.920 --> 00:38:49.500
Yep, I agree. I am now much more cognizant of these animal animal dynamics than I ever was before.

00:38:46.079 --> 00:38:57.420
And but it certainly opened up my mind about the role of infections and chronic infections and behavioral or mental health issues. And something I'll be looking out for certainly in patient care.

00:38:57.599 --> 00:39:06.690
I'm not saying I'm gonna test everybody for toxo, who is a CEO or an entrepreneur or risk taker, but it certainly is something that's gotten me thinking about that connection.

00:39:07.199 --> 00:39:08.969
Dennis, any closing ideas?

00:39:09.210 --> 00:39:24.750
Like I said earlier, I think this is just a very elegant study. I think it's just shows the complexity of all of those life cycles we have in nature and the connection between different species and parasites.

00:39:20.309 --> 00:39:38.190
And yeah, it's just very interesting. So do you think it's still a parasite? Or do you think it's like, what's the commensal? Or what's like, if you have something that somebody yawns Yeah, I don't know. I'm gonna leave that to, you know, the next science fiction movie. Chairman.

00:39:38.460 --> 00:39:44.670
Yeah, I think it's a parasite for now. And so, the parasitologist tell me different.

00:39:45.239 --> 00:39:46.889
I'm gonna defer to the experts.

00:39:46.889 --> 00:39:53.159
Yes, that one Paris, Paris otologist. Please comment in the in the in the comment section.

00:39:51.030 --> 00:39:53.159
Yeah, yeah.

00:39:53.219 --> 00:39:55.829
Well, thanks all for tuning in.

00:39:53.219 --> 00:40:12.030
This has been a lot of fun. We all we have some other ideas for papers we want to talk about other topics if there's top If you'd like to hear about, please go ahead and drop us an email, send us a message. And we are always interested in hearing about topics that might be of interest to you the listener. So thanks for tuning in. Thank you.

00:40:12.389 --> 00:40:13.139
Bye bye bye.

00:40:14.280 --> 00:40:22.409
Don't let the name West Nile virus tricky. Outbreaks of this fire has happened all across the United States and even in Texas.

00:40:22.860 --> 00:41:05.670
According to the CDC, there were almost 2700 cases in the United States and 77 cases in Texas in 2021. It's transmitted through mosquitoes, which means where your insect repellent during the summer and fall months, one in five people develop symptoms such as fevers, rash, and headaches. But some people can develop serious symptoms such as convulsions, vision, loss and paralysis. Seven Texans died last year to the West Nile virus. There are no vaccines or cures. So prevention is our best solution. And now, you know about the West Nile virus. This has been a viral minute.

00:41:07.590 --> 00:41:18.179
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