Speaker 1: Howdy, extraordinaries. We're recording this episode in July of twenty
Speaker 1: twenty six, in the middle of an outbreak of a
Speaker 1: parasite known as cyclospora. Cyclospora appears to have contaminated some
Speaker 1: of the United States's food supply and is causing intense
Speaker 1: diarrhea and those who have become infected. Apparently, when people
Speaker 1: hear intense diarrhea, they think Kelly Waidersmith, because wow, I've
Speaker 1: been hearing from a lot of you. I will take
Speaker 1: this as a compliment. So today we're going to talk
Speaker 1: about cyclospora, and we're also going to talk about some
Speaker 1: other diarrhea inducing parasites that are important for public health.
Speaker 1: Welcome to Daniel and Kelly's runny universe and ps as.
Speaker 1: Always remember I'm not a medical doctor. If you have
Speaker 1: diarrhea that concerns you, go see a real doctor.
Speaker 2: Hi.
Speaker 3: I'm Daniel. I'm a particle physicist who likes to think
Speaker 3: about aliens, and I eat a lot of bagged salad,
Speaker 3: or at least they used to. Hello.
Speaker 1: I'm Kelly Waiter Smith. I study parasites in space, and yes,
Speaker 1: I also eat a lot of bagged lettuces and have
Speaker 1: considered giving them to the geese.
Speaker 3: Instead considered, does that mean you're still eating preprocessed, pre
Speaker 3: washed lettuce?
Speaker 2: Yeah?
Speaker 1: It does?
Speaker 3: Wow?
Speaker 1: Interesting, Yeah, I live dangerously man.
Speaker 3: Well, when this whole thing broken the news, of course,
Speaker 3: the first person I messaged for advice about what I
Speaker 3: should and should not eat was my favorite parasitologist, which,
Speaker 3: of course is you, Kelly.
Speaker 2: Well.
Speaker 1: Thanks.
Speaker 3: Yes.
Speaker 1: When cyclostpora made the news as an outbreak in July
Speaker 1: twenty twenty six, it wasn't just you who sent me messages.
Speaker 1: It was all of my extended friends and family that
Speaker 1: I haven't heard from in years, and a lot of
Speaker 1: the extraordinaries. Apparently, when people hear diarrhea, they think Kelly.
Speaker 3: And is that something that pleased you? You're like, look,
Speaker 3: I have relevant expertise.
Speaker 1: Finally, the funny thing is I don't have relevant expertise.
Speaker 1: It took a long time to prepare for this episode.
Speaker 1: These are not parasites that I've worked on or thought
Speaker 1: about much. Ever. The other interesting connection here is that
Speaker 1: the one other time in my life that a bunch
Speaker 1: of people I hadn't talked to for a very long
Speaker 1: time thought of me and reached out was when Tugo
Speaker 1: Bell brought back their Mexican pizza.
Speaker 3: What's the Kelly connection there?
Speaker 1: I guess I really liked Mexican pizzas, and I didn't
Speaker 1: realize how much I liked them because a bunch of
Speaker 1: people were like, Kelly, the Mexican pizza's back, and I
Speaker 1: was like so, and they're like, you loved those, and
Speaker 1: I was like, oh, I loved those. And it's kind
Speaker 1: of interesting the things that people remember about you. They
Speaker 1: did not seem important to you at the time.
Speaker 3: Well, I have a theory about that based on very
Speaker 3: little data, which is that you're very polite person and
Speaker 3: a very positive person. So maybe these folks just like
Speaker 3: went to Taco Bell with you one time and you
Speaker 3: just like enthused about your food because you're a very
Speaker 3: positive person, and that made an impression on them.
Speaker 1: Could be yeah, could be thank you. I do get
Speaker 1: I get excited about just about everything. You know, we
Speaker 1: do have it pretty good in general.
Speaker 3: Yeah, that's true. It is amazing that I could just
Speaker 3: like go to the store and buy a bag of
Speaker 3: pre washed, pre mixed salad and it's pretty good. I
Speaker 3: used to make salads every single day from scratch. You know,
Speaker 3: you buy all the ingredients, you wash them, you chop them.
Speaker 3: It was a lot of work, but I was dedicated
Speaker 3: to eating salads. And then with the rise of bagged salads,
Speaker 3: I was like, this is amazing. And I've often wondered, like,
Speaker 3: what is the infrastructure behind this? Is it really expensive
Speaker 3: for the environment? Is it opening us up to weird
Speaker 3: new bugs and parasites? And I guess now we know, well.
Speaker 1: I don't necessarily know that the rise of bag salads
Speaker 1: is the thing you can put your finger on. Were like,
Speaker 1: this is why we are at increased risk. So you know,
Speaker 1: in this case, it was shredded lettuce that got sent
Speaker 1: to Taco Bell, so it wasn't even like bagged mixed salads.
Speaker 1: And you know, you can get sick if you go
Speaker 1: to a farmer's market and you buy lettuce that people,
Speaker 1: you know, cut off the ground and threw in a bag,
Speaker 1: and you're just buying it that way, it's not mixed
Speaker 1: up with other stuff. The bad news here, Daniel, is
Speaker 1: that there's a lot of routes from butts to mouths.
Speaker 3: All right, well, let's dispense with Daniel's unfounded theories of
Speaker 3: the demise of society and get into the episode. It
Speaker 3: wasn't just me who contacted you about this, didn't We
Speaker 3: also hear from listeners.
Speaker 1: We heard from so many listeners. Here is a subset
Speaker 1: of folks who thought about diarrhea and then thought about Kelly.
Speaker 4: Hi, Daniel Kelly. This is Matt from northwest Indiana. I'm
Speaker 4: curious about cryptosporidiosis. Hopefully I said that right. That name
Speaker 4: is horrible. So several years ago now, when my wife
Speaker 4: Sydney and I were still in college, she was visiting
Speaker 4: Peru on a month long class trip. She had a
Speaker 4: great time, but it was difficult adjusting to the dietary
Speaker 4: differences of the region. Leafy Green's are ruffage of any
Speaker 4: kindra and short supply, so when they did find in
Speaker 4: a place serving salad, most of the class indulged heavily.
Speaker 4: Even before she returned home, she was not feeling well.
Speaker 4: She had stomach cramps, fatigue, and throughout her first evening
Speaker 4: back in the States, she was overcome with very intense diarrhea. Naturally,
Speaker 4: we went to the hospital and she was given fluids
Speaker 4: and they confirmed it was something called cryptosporidiosis or simply crypto, which,
Speaker 4: by the way, horrible name. I assumed the root is
Speaker 4: Greek or Latin. That probably means something non threatening, but
Speaker 4: it immediately made me think of Tales from the crypt
Speaker 4: which was childhood nightmare fuel for me.
Speaker 3: But I digress.
Speaker 4: Sydney had to do a few interviews with folks from
Speaker 4: the CDC tracking where she went in Peru and if
Speaker 4: any other students complained of similar symptoms, which several of
Speaker 4: them did. But they also stressed heavily that this parasite
Speaker 4: could have killed her, which at first felt kind of dramatic,
Speaker 4: but she was definitely dehydrated. Would a crypto fatality be
Speaker 4: caused by dehydration or something else? I suppose my question
Speaker 4: in the broadest senses, what is this bugs deal? What
Speaker 4: did it do to her to produce these symptoms? Did
Speaker 4: it likely come from icky water contaminated produce? A recent
Speaker 4: episode of The Pod on cholera shook this memory loose,
Speaker 4: as the symptoms sounded pretty similar. But are the parasitic
Speaker 4: mechanisms the same? Thanks to you both, love the show.
Speaker 3: Hello President of Parasites. How worried should I be about cyclospora?
Speaker 3: I eat a lot of salads and I'm lazy, so
Speaker 3: bag salads are very convenient should I change my habits
Speaker 3: or is this still very rare and remote? Thank you.
Speaker 2: Sarah Taber is a farm activist worth listening to. She
Speaker 2: ran for North Carolina Commissioner of Agriculture in twenty twenty four,
Speaker 2: which is how I started following her. If she's talking
Speaker 2: about a widespread outbreak of explosive diarrhea, I think that's
Speaker 2: something you really should explore as a public service. Is
Speaker 2: it cryptosporidium nerovirus? A parasite given a leg up by
Speaker 2: the climate crisis? Inquiring minds want to know. However, we
Speaker 2: definitely need an answer to the explosive diarrhea outbreak. In
Speaker 2: my lawyer days, I worked on Clean Water Act cases
Speaker 2: with the NRDC. I don't know if it's an explanation
Speaker 2: for the current outbreak on the East Coast, but I
Speaker 2: know that in California, concentrated animal feed operations CAFOs in
Speaker 2: the Central Valley crowd thousands of cattle into relatively confined
Speaker 2: areas which are surrounded by farmland cattle poop and the
Speaker 2: runoff from that poop. If it's not carefully confined, it's
Speaker 2: not can reach groundwater. Downstream Crops, especially leafy greens, can
Speaker 2: uptake that contaminated water through their roots, which is why
Speaker 2: washing the greens when you get them home doesn't remove
Speaker 2: the bacteria. I hate CAFOs, and the cattle probably aren't
Speaker 2: too thrilled either.
Speaker 5: Hey, Dan, knowing, Kelly gloy Dan checking in. I've got
Speaker 5: a question for you guys today about parasites. Why father
Speaker 5: often avoids eating fruits because he's concerned about getting parasites
Speaker 5: from them. Can we actually get parasites simply by eating fruit?
Speaker 5: If so, what parasites are they and what fruits would
Speaker 5: they typically be found on?
Speaker 3: Thank you? All right, So Kelly tell us how big
Speaker 3: of a problem is this.
Speaker 1: Well it's pretty big. So according to the World Health Organization,
Speaker 1: one point seven billion kiddos suffer from diarrheal diseases every year.
Speaker 3: One point seven billion with a.
Speaker 1: Bee billion with a bee.
Speaker 3: Like a big fraction of humanity. We're talking about a.
Speaker 1: Big fraction of humanity has a diarrheal disease. And this
Speaker 1: could also be like ecoli. It's definitely not just cyclospora.
Speaker 1: There's lots of parasites and pathogens that can cause diarrhea,
Speaker 1: but diarrhea globally is still a huge problem.
Speaker 3: Wow. Does that mean like that the volume of diarrhea
Speaker 3: produced annually is like, no, a pretty big number in
Speaker 3: terms of like leaders or swimming pools or something.
Speaker 1: Yeah, I was gonna say, I don't know the number
Speaker 1: of Olympic swimming pools full of diarrhea that our species
Speaker 1: creates each year, but that's probably a lot. It's probably
Speaker 1: a big number, but you know, and so that is funny.
Speaker 1: But about half a million kids under the age of
Speaker 1: nine every year die from diarrheal diseases. I know, I'm
Speaker 1: such a stink and ray of sunshine, but a lot
Speaker 1: of these cases of diarrhea could be avoided if people
Speaker 1: had safe drinking water and better sanitation. And that's going
Speaker 1: to be a theme for today. But because I am
Speaker 1: a parasite person, we're going to for today stay away
Speaker 1: from the bacteria and viruses that cause diarrhea and focus
Speaker 1: on the parasites. And so what we're talking about here
Speaker 1: are single celled eukaryotic critters, so they've got you know,
Speaker 1: a nucleus, membrane bound organelles, stuff like that, rather than
Speaker 1: bacteria and viruses. So we're talking about stuff that like
Speaker 1: is distantly related to malaria. For example, just to help
Speaker 1: you get like a foothold. These are small. You can't
Speaker 1: see them with the naked eye.
Speaker 3: Wait, malaria is caused by a parasite.
Speaker 1: Malaria is caused by a parasite that is, you know,
Speaker 1: distantly related but like somewhat related to the parasites that
Speaker 1: we're talking about today.
Speaker 3: All right, So my calculations suggest that there's about ten
Speaker 3: thousand Olympic sized swimming pools of diarrhea produced by humans
Speaker 3: every year. Wow, and now you're telling me that we're
Speaker 3: only focusing on a fraction of that that's produced by
Speaker 3: parasitic infections, not parasitic infections, parasitic what's the word parasit?
Speaker 1: Infections with parasites?
Speaker 3: Okay, all right, yeah, what fraction of those ten thousand
Speaker 3: swimming pools do you think probably come from parasites? Or
Speaker 3: we're dealing with the bulk of the diarrhea or a
Speaker 3: little offshoot, a little rivulet of it.
Speaker 1: Oh god, all right, let's say somewhere in between. So
Speaker 1: sometimes it can be hard to identify the particular cause
Speaker 1: of a diarrheal disease, and so you aggregate. I'll be
Speaker 1: giving you some numbers, mostly US based for the parasites
Speaker 1: we're talking about today to help you get a handle
Speaker 1: on how common these things are.
Speaker 3: All right, so we're focusing on the parasites and what
Speaker 3: are the parasites that mostly cause diarrhea?
Speaker 1: So before we get into the species, let's go ahead
Speaker 1: and do like an overview just to make it easier,
Speaker 1: because if we go into too much detail about the species,
Speaker 1: I think it's easy to get sort of bogged down
Speaker 1: with information. So let's talk about some like commonalities first
Speaker 1: to make this a little easier to digest. So, for
Speaker 1: all of the poor parasites we're talking about today, symptoms
Speaker 1: they cause include watery diarrhea, stomach pain, nausea, and vomiting.
Speaker 1: You usually get a little bit of a fever and
Speaker 1: you don't have much of an appetite. We don't have
Speaker 1: vaccines for any of these, oh, which sucks. And they
Speaker 1: all take about a week for symptoms to show up
Speaker 1: after you get infected. So we're gonna talk about what
Speaker 1: they're doing to your gut in particular. But this week
Speaker 1: between ingestion and the onset of symptoms is part of
Speaker 1: what makes it so hard to figure out where outbreaks start.
Speaker 3: All right, Well, I'm really curious, like why it takes
Speaker 3: a week to get the symptoms, and why exactly they
Speaker 3: cause diarrhea, Like is it a byproduct? Are they intentionally
Speaker 3: causing diarrhea because it helps, you know, with their life
Speaker 3: cycle or whatever. Dig into the details for me.
Speaker 1: Oh yes, okay, So you got to hold on a
Speaker 1: little bit. For each one of them, they induce diarrhea
Speaker 1: for slightly different reasons, and they're doing slightly different things
Speaker 1: inside your gut, which I think is absolutely fascinating. And
Speaker 1: I'm gonna, you know, to cut to the chase. Nobody's
Speaker 1: gonna be surprised to hear me say. We don't understand
Speaker 1: really well what is exactly causing the diarrhea, but the
Speaker 1: things that they're doing when they're inside of our intestines
Speaker 1: make it pretty easy to imagine why diarrhea is happening.
Speaker 1: So we will get to that, I promise.
Speaker 3: All right, So how do we run into these critters?
Speaker 3: Why do they end up in our guts? Yeah?
Speaker 1: So for all of them, we're talking about the fecal
Speaker 1: oral route again, which we'll called poop to mouth. Yeah.
Speaker 1: I know, it's so gross, it's so gross, but there's
Speaker 1: so many ways these parasites can get to us. They
Speaker 1: can get to us by changing diapers. So these are
Speaker 1: parasite you have to be really worried about in like
Speaker 1: childcare settings. These are parasites that you can get by
Speaker 1: drinking water at the public pool, which is why if
Speaker 1: anyone poops in the pool, they immediately shut the whole
Speaker 1: pool down. You know, like the first time someone shut
Speaker 1: a pool down because a baby pooped in the pool,
Speaker 1: my first thought was, wasn't that what the chlorine is for?
Speaker 1: But like, you need a lot more chlorine to kill
Speaker 1: these parasites, and some of them are resistant to chlor
Speaker 1: which is a real pain. So drinking water from a
Speaker 1: public pool, drinking water from a beautiful bubbling brook or
Speaker 1: a river or a lake, there's wild animals out there
Speaker 1: pooping or you know, if we're talking about something like cyclospora,
Speaker 1: it's because human feces accidentally ended up getting on our
Speaker 1: food and then gets into our face.
Speaker 3: I gotta say, Kelly, for like how gross it is
Speaker 3: the concept of like, you know, the poop to mouth
Speaker 3: throughout Nobody wants to be eating poop and it's dangerous.
Speaker 3: Why aren't we better at keeping poop out of our
Speaker 3: water and out of our food, like it seems like
Speaker 3: it should be a priority.
Speaker 1: Yes, I know, right, But okay, so before we talk
Speaker 1: about how it goes wrong and why that's frustrating, I
Speaker 1: do think we should note that we actually do a
Speaker 1: good job most of the time. Like the reason the
Speaker 1: cyclospora thing is in the news is because something fell
Speaker 1: apart and now we have cyclospora, and it's news because
Speaker 1: it doesn't happen often's you know, most of the time,
Speaker 1: at least if you live in the United States, you
Speaker 1: can take a sip of water from the faucet and
Speaker 1: you don't have to worry about getting a parasite that's
Speaker 1: going to give you diarrhea. So one of the problems
Speaker 1: for some of these parasites is that it's not just
Speaker 1: humans that are in the life cycle of the parasite. So,
Speaker 1: for example, if you're out and you take a drink
Speaker 1: from a beautiful river, you might be ingesting a parasite
Speaker 1: that was put there by beavers. There's another parasite we're
Speaker 1: going to talk about today that's a really big problem
Speaker 1: for cattle. And so if you have cattle that are
Speaker 1: anywhere in a watershed and the rain washes cattle poop
Speaker 1: into a stream that subsequently feeds a public water supply,
Speaker 1: then you've got a problem there too.
Speaker 3: But if you're taking water from a stream for a
Speaker 3: public water supply, you gotta clean it. You can't just
Speaker 3: be like, look, we found some water. I mean, if
Speaker 3: I'm out hiking and I see a stream, I don't
Speaker 3: just like put my face into it, right, I like
Speaker 3: only filter it or treat it or whatever. So why
Speaker 3: aren't we cleaning our public water to prevent there from
Speaker 3: being pooping it?
Speaker 1: Okay, but again, we are cleaning our water, and that's
Speaker 1: why this doesn't have and often but yeah, well, so
Speaker 1: some outbreaks that have happened in the past have happened
Speaker 1: at facilities where some part of their water treatment equipment
Speaker 1: had broken down and they just didn't realize it yet,
Speaker 1: and then people started getting sick and they didn't realize it.
Speaker 1: And then sometimes the problem is that, like to kill
Speaker 1: these parasites takes a lot of chlorine, and maybe not
Speaker 1: enough was added at a certain time, and so you know,
Speaker 1: this is like a system that needs constant surveillance and vigilance,
Speaker 1: and sometimes that falls apart.
Speaker 3: I was hearing today an interview on NPR with an
Speaker 3: expert at the FDA who's saying that they just don't
Speaker 3: have the resources to like check if farms are following protocols.
Speaker 3: Like farmers, if they see a pile of animal poop
Speaker 3: on their iceberg lettuce field are supposed to like coordinate
Speaker 3: off and nobody's supposed to ever get that lettuce that's
Speaker 3: near the poop. But the FDA doesn't even have the
Speaker 3: resources to send inspectors to visit farms every three years. Wow,
Speaker 3: Like that's too much for the FDA to handle. So basically,
Speaker 3: I think we're relying on farms and farmers and mega
Speaker 3: corporations to police themselves and we always know how well
Speaker 3: that goes.
Speaker 1: Yeah, Okay, so then let's jump to some recent regulatory changes.
Speaker 1: We can talk about that now. So, like you were
Speaker 1: talking about, on farms, if there is poop in the field,
Speaker 1: just supposed to coordinate off. Yeah, But if somebody has
Speaker 1: pooped in the field, that probably means you have not
Speaker 1: given them access to a toilet, or you have not
Speaker 1: given them sufficient breaks so that they can get to
Speaker 1: a toilet. It could just mean someone got lazy, but like.
Speaker 3: Or it could be animal poop also right where.
Speaker 1: It could be animal poop also, right, But you know,
Speaker 1: animal poop kind of looks like soil, right, and after
Speaker 1: a little while it becomes soil. That's like part of
Speaker 1: the process. And so I think it's easy to miss
Speaker 1: these things. And yes, it does sound like there's a
Speaker 1: shortage of people. And an increasing problem here is that
Speaker 1: in twenty twenty five, the Trump administration cut back a
Speaker 1: lot of jobs, and those jobs got cut at the federal, state,
Speaker 1: and local level, And so there's a lot of reports
Speaker 1: from public health both officials right now saying look, it's
Speaker 1: always been hard to do our job, and it's even
Speaker 1: harder to do our job now because we don't have
Speaker 1: the people power that we need. You know, we were
Speaker 1: already underpowered before. Another problem is that there are different
Speaker 1: places where you are required to report food born illness. So,
Speaker 1: for example, if someone comes into your doctor's office and
Speaker 1: you decide that they've encountered cyclospora in twenty twenty five,
Speaker 1: you would need to report that to at least two places.
Speaker 1: I believe one of them was food net, and so
Speaker 1: food Net kept track of a bunch of different food
Speaker 1: born illnesses. But as of twenty twenty five, the Trump
Speaker 1: administration said you don't need to report to food net anymore.
Speaker 1: There's only two diseases that you need to report to
Speaker 1: food nets. Their argument was that there are other organizations
Speaker 1: that deal with food born illnesses, and to be fair,
Speaker 1: the National Notifiable Diseases Surveillance System is a system still
Speaker 1: in place where cyclospora should be reported to if you
Speaker 1: happen to encounter it, but you used to also need
Speaker 1: to report it to food net. And so the more
Speaker 1: connections we have between the people whose job it is
Speaker 1: to try to make sure these diseases aren't getting to us,
Speaker 1: and once they do get to us, that we identify
Speaker 1: the source and get it off of our shelves quickly,
Speaker 1: like that system has become less robust in the last
Speaker 1: year or so, not ideal, and so a bunch of
Speaker 1: public health officials are saying, in the past, we probably
Speaker 1: would have nailed this down sooner. But as we'll talk about,
Speaker 1: it's hard to nail down the sources of these things.
Speaker 1: So real quick, let's talk about what happens when an
Speaker 1: outbreak starts. So you know, some doctor's office, for example,
Speaker 1: might identify one or more cases of cyclospora or some
Speaker 1: other food born illness that we're talking about today or
Speaker 1: poop to mouth illness, and then they have to report
Speaker 1: it to the state and federal levels in some cases
Speaker 1: depending on the disease, and then public health officials will
Speaker 1: go and they'll interview anyone who has been identified as
Speaker 1: having encountered this parasite and become infected by it.
Speaker 3: Interview meaning like, tell us everything you've eaten the last
Speaker 3: three weeks and every time you've dipped your finger in
Speaker 3: a stream or something.
Speaker 1: Yes, right, and you've identified why this is so hard? Right?
Speaker 1: And so if the deal was they were looking at
Speaker 1: something where you eat it and then twelve hours later
Speaker 1: you have horrible diarrhea, then you'd only have twelve hours
Speaker 1: of like what did you eat? Where did you go?
Speaker 1: To think about? But if the illness takes one to
Speaker 1: two weeks to start showing symptoms, you've got to remember
Speaker 1: like in the last two weeks, did I go to
Speaker 1: Taco Bell? Did I go to Burger King? How many
Speaker 1: bag salads did I eat?
Speaker 3: Did I did I go swimming?
Speaker 1: Did I go swimming?
Speaker 2: Right?
Speaker 1: Did I have sex with a partner where I interacted
Speaker 1: with their buttole at all like I'm sorry, but that
Speaker 1: is another common routes that you find on like the
Speaker 1: CDC and the FDA web pages, Like, there's just a
Speaker 1: lot of different routes through which you can encounter a
Speaker 1: lot of these kinds of parasites. And then it's someone's
Speaker 1: job to go through all of those data and look
Speaker 1: for commonalities, like, Okay, everybody who got cyclospora, you know,
Speaker 1: went to Taco Bell for example, they got something with
Speaker 1: lettuce in it. But to be clear, that data are
Speaker 1: almost never exactly that straightforward, like there will be somebody
Speaker 1: will say to you like, yes, I went to Taco Bell,
Speaker 1: but my brother was with me. We had the exact
Speaker 1: same thing, and he doesn't have diarrhea, right, And a
Speaker 1: lot of these parasites, for some people, they're entirely asymptomatic,
Speaker 1: so they won't get diarrhea even though the parasite is
Speaker 1: living in their gut. We don't understand why that's crazy.
Speaker 3: Some people just win the parasite lottery.
Speaker 1: Yes, right, which makes it so hard to like, you know,
Speaker 1: know what signal is the signal you should be paying
Speaker 1: attention to, because you know, you can imagine if you say, like,
Speaker 1: all right, a bunch of people ate a Taco Bell,
Speaker 1: but this person went with their brother, they ate the
Speaker 1: same thing, the brother didn't get sick. Probably it's not
Speaker 1: the taco bell.
Speaker 3: Right, Yeah, that'd be useful to rule it out.
Speaker 1: That would be useful to rule it out. But another
Speaker 1: thing that makes it tough is that if it takes
Speaker 1: seven to fourteen days for symptoms to show up, usually
Speaker 1: in that amount of time, whatever it was that was
Speaker 1: causing the illness has expired and been removed from the shelves.
Speaker 1: And so ideally what you want is to like have
Speaker 1: someone who has diarrhea, which of course you don't want that,
Speaker 1: but if they do, you'd like to collect some of
Speaker 1: their feces, extract the parasites, get the whole genome for
Speaker 1: the parasite, and then find the source that you think
Speaker 1: cause the infection. Extract the parasite from, for example, that lettuce,
Speaker 1: and then match up the genome in the lettuce with
Speaker 1: the genome coming out of the person. So you can say, bam,
Speaker 1: this is the source. Does that make sense?
Speaker 3: I see. So you're using the DNA of the parasite
Speaker 3: as like a tracker. Yep. You're saying there's a community
Speaker 3: parasites out there. They'll have slightly different DNA. If I
Speaker 3: can match the DNA what's in my gut to the
Speaker 3: DNA of the parasite found in this stream, that I
Speaker 3: can say this was the source that ended up.
Speaker 1: In my gut right or for the example that's sort
Speaker 1: of plaguing the United States right now, if you can
Speaker 1: find a farm where the parasite that's in the lettuce
Speaker 1: on that farm matches the parasite in someone's gut up
Speaker 1: in Michigan, then you can say, Okay, probably the lettuce
Speaker 1: from this Tailor Fields farm in Mexico is the source.
Speaker 1: In this case, it seems like the lettuce came from
Speaker 1: Taylor Farms to Mexico. My Spanish is really good, everybody,
Speaker 1: and so and so they probably need to be held
Speaker 1: to the same standards as US based producers and tailor
Speaker 1: farms should be sending people to go check out what's
Speaker 1: happening from time to time. But it looked like something
Speaker 1: fell apart, and so another step that happens here that
Speaker 1: sort of in between what we've talked about so far,
Speaker 1: is that if it turns out that you think, for example,
Speaker 1: it's lettuce from Taco Bell, then you say, okay, Taco Bell,
Speaker 1: where did you get your lettuce from. You're supposed to
Speaker 1: be keeping careful records, right, and so they'll tell you,
Speaker 1: all right, we got it from Tailor Farms. And so
Speaker 1: then you'll say, all right, Taylor Farms, which bags of
Speaker 1: lettuce did you send to Taco Bell and where did
Speaker 1: the lettuce in each of those bags come from? And
Speaker 1: they're supposed to be keeping super detailed records that they
Speaker 1: can tell you exactly which farm the lettuce came from,
Speaker 1: and that could change over time.
Speaker 3: Sounds like a good plan.
Speaker 1: Sounds like a good plan, right, And then you have
Speaker 1: to go and actually visit those farms and try to
Speaker 1: find it. But again, these symptoms could be showing up
Speaker 1: weeks after and so a lot in a lot of cases,
Speaker 1: you're not going to find the smoking gun because the
Speaker 1: lettuce has expired, it's been thrown out, it's in the trash.
Speaker 1: You can't necessarily find those connections anymore. So for the
Speaker 1: outbreak we're having right now, it appears that what happened
Speaker 1: is that they've tracked it back to a particular farm.
Speaker 1: They haven't been able yet to get a positive sample
Speaker 1: where they say definitely, we found cyclospora at Tailor Farms.
Speaker 1: To Mexico's farm, and it matches with what's in the
Speaker 1: gut of somebody up in Michigan, but they have been
Speaker 1: able to say that. Ever, you know, pretty much everybody
Speaker 1: who has had cyclospora, all of the evidence that we
Speaker 1: have suggests that it routed through Taco Bell through their
Speaker 1: lettuce to tailor farms lettuce that came from Mexico.
Speaker 3: All right, so let's take a break because I need
Speaker 3: a break, so much poop on the brain. And when
Speaker 3: we come back, we'll dig into the various critters that
Speaker 3: can give you diarrhea. Okay, we're back, and we're talking
Speaker 3: about our VCS covered world. You like to think we
Speaker 3: live in a world that's mostly clean and sparkling, but
Speaker 3: in reality, there's poop everywhere, isn't there, County.
Speaker 1: There's poop everywhere, almost everywhere, and in the United States
Speaker 1: about a million people each year get infected by the
Speaker 1: first parasite we're going to talk about, which is Giardia. Daniel,
Speaker 1: do you want to guess when giardia was seen for
Speaker 1: the first.
Speaker 3: Time, the first time it was ever seen, like in
Speaker 3: human history? Yeah, oh boy, I'm guessing.
Speaker 1: Like with the human eye.
Speaker 3: Oh, with the human eye I'm guessing the first cases
Speaker 3: of giardi are probably like Babylon, probably, but if Giardia
Speaker 3: is very small, it probably required the invention of the microscope.
Speaker 3: So I'm guessing a couple hundred.
Speaker 1: Years ago, Yeah, something like that. But you want to
Speaker 1: guess who who looked at almost everything that came out
Speaker 1: of him and reported back to the Royal Society?
Speaker 3: Is it? What's his name? Van Lewinhos.
Speaker 1: Yes, yes, he had diarrhea. He put it under the
Speaker 1: microscope and he saw giardia and was.
Speaker 3: Like, oh, historical diarrhea.
Speaker 1: Amazing, historical diarrhea.
Speaker 3: Anyway, all right, is there a museum somewhere that has
Speaker 3: like a sample of his original diarrhea that changed the world?
Speaker 1: Sure, hope not. Definitely doubt it. And it didn't change
Speaker 1: the world because he didn't make the connection between what
Speaker 1: he was seeing in his poop and the cause of
Speaker 1: the giardia.
Speaker 3: Because you know, there's a museum for almost everything, Like
Speaker 3: I've been to Iceland, I've been to the Phallic Museum,
Speaker 3: you know.
Speaker 1: Amazing.
Speaker 3: Yeah, yes, I have a picture of my kids standing
Speaker 3: next to a blue whale fallice. It's impressive.
Speaker 1: Nice the bone, right, yes, yeah.
Speaker 3: Exactly so I imagine somewhere there's a museum of diarrhea.
Speaker 1: You know, I gotta be honest, I wouldn't be opposed
Speaker 1: to that as a museum idea, because I feel like,
Speaker 1: you know, diarrhea has taken away many people throughout history,
Speaker 1: you know, whether it was cholera or like dysentery during wars,
Speaker 1: and so I feel like you could have a pretty
Speaker 1: interesting human history story told through the museum of diarrhea.
Speaker 1: And like one of the greatest human victories in my
Speaker 1: opinion ever, is like our amazing sewage systems, And so
Speaker 1: I would go to that museum. Daniel, Okay, sign me up.
Speaker 3: So tell us about Van Luin Hook's diarrhea.
Speaker 1: Oh well, that's all I had to say on the
Speaker 1: topic of Van Lewin Hook's diarrhea. But giardia is unique
Speaker 1: amongst the diarrheal parasites, and that is the only one
Speaker 1: where the descriptions of symptoms include really awful farts and stinky,
Speaker 1: greasy floating poops. And I gotta tell you, I spent
Speaker 1: a lot of time trying to figure out what it
Speaker 1: was about giardia in particular that resulted in stinky, greasy,
Speaker 1: floating poops as opposed to the other kinds of poops.
Speaker 1: I couldn't get to the bottom of it, Daniel. I
Speaker 1: spent hours, and I could not get to the bottom
Speaker 1: of it.
Speaker 3: You mean like people don't know or you couldn't find
Speaker 3: the answer.
Speaker 1: So when I was looking up how does giardia cause diarrhea?
Speaker 1: I found this quote. The mechanisms by which giardia causes
Speaker 1: diarrhea and intestinal melabsorption are probably multifactorial and not yet
Speaker 1: fully elucidated. We don't know, wow, But what we do
Speaker 1: know is that when it gets into your intestines, it
Speaker 1: has this disc, and it uses the disc to stick
Speaker 1: to the little like finger like projections that go out
Speaker 1: into your stomach across which things are absorbed. These are
Speaker 1: called villi, and it sticks to the villi and it
Speaker 1: causes them to flatten and start sticking together. And so
Speaker 1: the surface that you used to use to like orb
Speaker 1: stuff into your body now have much less surface area
Speaker 1: because they're like smoosed and touching each other, and that
Speaker 1: makes it harder for your body to absorb the food
Speaker 1: and the water that you drink, so presumably more of
Speaker 1: it just passes right through. But again, the connection between
Speaker 1: knowing that it's like messing up the villai And the
Speaker 1: exact reason why you get this particular kind of diarrhea
Speaker 1: is something I don't think that we know yet.
Speaker 3: And when you say it causes stinky poops, like, m
Speaker 3: m all poops are stinky. So is this like especially
Speaker 3: stinky or like stinky in a weirdly gardia fashion, Like
Speaker 3: could a giardia specialist smell a poop and be like, oh, yeah,
Speaker 3: that's giardia.
Speaker 1: I think yes. Right, So I had a roommate who
Speaker 1: went to Guyana to go visit her girlfriend, and when
Speaker 1: she came back, first she got dumped, but second she
Speaker 1: got giardia, and so it was like a particularly bad
Speaker 1: trip for her. But she complained that like her poop
Speaker 1: smelled so weird. Like, wait, you know, we've all had
Speaker 1: diarrhea at some point in our life, right, but this
Speaker 1: was different. And I fortunately didn't live with her at
Speaker 1: this point. I moved in with her later, but anyway,
Speaker 1: so yeah, I think it's it's a unique odor apparently,
Speaker 1: all right.
Speaker 3: So we know these things are like attaching to the
Speaker 3: lining of the stomach, and that obviously is going to
Speaker 3: affect your digestion. We don't understand exactly why it causes
Speaker 3: weird poops or diarrhea or whatever, But what's the whole
Speaker 3: life cycle? Why are they attaching to the lining of
Speaker 3: our stomach? How does that benefit them?
Speaker 1: Yeah, so the way that you get it is you
Speaker 1: ingest like assist stage that's in the water, and it
Speaker 1: can be put in the water by other people who
Speaker 1: pooped in the water. It can be put in the
Speaker 1: water by beavers. Beavers are pretty common carriers of this parasite,
Speaker 1: and so they're doing their little beaver thing. They poop
Speaker 1: in the water, and then you think, oh, it's so
Speaker 1: pristine out here. I'm going to take a drink without
Speaker 1: first boiling and or filtering my water.
Speaker 3: You know, I had no reason to dislike beavers until today.
Speaker 3: I was just one hundred percent pro beaver. And now
Speaker 3: I'm like, wow, there's something in the negative column for
Speaker 3: be as they poop in the water.
Speaker 1: I'm still one hundred percent pro beaver. Man Like, our
Speaker 1: poop probably gets in the water sometimes too, Like, it's
Speaker 1: not their falts, it's Garadya's fault.
Speaker 3: I'm not saying it swung me all the way to
Speaker 3: anti beaver. I'm saying now there is something in the
Speaker 3: negative column, whereas it used to be just everything was
Speaker 3: good about beavers.
Speaker 1: Okay, all right, well you do you I still like
Speaker 1: beaver's We have a couple families of beavers on our
Speaker 1: property and I yeah, and I actually saw one of
Speaker 1: their dams. The recent like monsoon style rains we got
Speaker 1: here in Virginia in the middle of our giant flood
Speaker 1: washed out their dam, which was I hope they're rebuilding.
Speaker 3: And don't you drink well water? Is that potentially contaminated
Speaker 3: by beaver poop?
Speaker 1: Yes? Yeah, so you do have to worry about that
Speaker 1: if you live in like a wilderness ye kind of area,
Speaker 1: you have to be careful. We do check our water
Speaker 1: once a year. Oh, but I am more concerned with
Speaker 1: the proximity between my septic field and my well water,
Speaker 1: which is still like more than sufficiently far away up
Speaker 1: to code or whatever. But yes, when you live out
Speaker 1: in an area like I do, you do need to
Speaker 1: get your water tested regularly to see if human feces
Speaker 1: or animal feces have managed to get in.
Speaker 3: Wow.
Speaker 1: But anyway, so you accidentally consume it, it passes through
Speaker 1: the stomach and when it gets to the intestine, it
Speaker 1: breaks out of a cyst. Okay, yeah, so it's got
Speaker 1: to get through the stomach first. I don't know why
Speaker 1: it's the intestines in particular that are the best place
Speaker 1: for it to live, but because it needs to produce
Speaker 1: cysts that go back into the environment. Attaching to the intestines,
Speaker 1: replicating like crazy, producing more cysts and inducing diarrhea seems
Speaker 1: like a pretty good way to get your babies back
Speaker 1: out into the environment.
Speaker 3: But why do you need to induce diarrhea? I mean,
Speaker 3: you're in the intestines, you produce more cysts, They can
Speaker 3: just go in the normal poop, right, Why do you
Speaker 3: have to interfere? Why do you have to cause cramps
Speaker 3: and make everybody so miserable?
Speaker 1: Well, I can imagine diarrhea being more likely to get
Speaker 1: like washed into a waterway or get like, you know,
Speaker 1: maybe you are walking along a river and if you
Speaker 1: need to have your normal bowel movement, you'll be like,
Speaker 1: I can make it home. But if you've got diarrhea,
Speaker 1: you're not making it home. And so it just happens
Speaker 1: where it happens. And you know, I think for some
Speaker 1: of these things, you look it's tempting to look for
Speaker 1: evolutionary reasons, and I can imagine.
Speaker 3: That I'm still stuck on diarrhea colon. It happens where it.
Speaker 1: Happens, right, Maybe that should be the title of this episode.
Speaker 3: Or like a T shirt or something.
Speaker 1: Yeah, something like that, something uplifting. But anyway, so that's
Speaker 1: the life cycle, all right. If you go to the vet,
Speaker 1: you might hear that your dog or cat has giardia.
Speaker 1: That doesn't necessarily mean that you need to worry. The
Speaker 1: dog and cat versions don't usually jump to people. But
Speaker 1: you should always wash your hands after dealing with animal waste,
Speaker 1: and you know, don't let your dogs put their butts
Speaker 1: on your pillows. This is like one of my This
Speaker 1: is one of the things where I feel like I
Speaker 1: go to loads of houses and people's dogs are up
Speaker 1: on their beds with their butts on their pillows, and
Speaker 1: I'm like, friends, no, your face goes there later.
Speaker 3: Well, also, a lot of people kiss their dogs or
Speaker 3: let their dogs lick their faces, and I'm like, have
Speaker 3: you seen where your dog's face has been because it's
Speaker 3: been up its own butt or its neighbors. But yeah,
Speaker 3: and so yeah, people should think about that.
Speaker 1: They should. Yes, I'm going on the record but.
Speaker 3: In terms of giardia, you get it in you, you
Speaker 3: get diarrhea. Does it naturally just progress? Does your immune
Speaker 3: system eventually attack these things or do you just have
Speaker 3: garda forever unless you take some anti parasitic medicines.
Speaker 1: Yeah. So some people are asymptomatic. Wow, and we'll have
Speaker 1: it for a long time. Some people get really bad symptoms,
Speaker 1: and we do have medication that you can give them
Speaker 1: to treat it. And then some people it will go
Speaker 1: away on its own. But again I am not a
Speaker 1: medical doctor. So if you think you have giardia, let
Speaker 1: your doctor tell you if you should see if it
Speaker 1: goes away on its own, or if you should be
Speaker 1: taking some medication for that. Sorry, thanks for bleeping that mat.
Speaker 1: And look, I included a photo because if you are
Speaker 1: a parasitologist, we tend to think giardia is one of
Speaker 1: the more charismatic looking parasites. What do you see the picture? Yes, So,
Speaker 1: as to a nuclei that look like eyes in the
Speaker 1: picture that I sent you, it doesn't have there's like
Speaker 1: another organelle that kind of looks like a smiling mouth.
Speaker 1: It's missing in this artist's rendition. And it also has
Speaker 1: multiple pairs of flagello, which are long like hair like
Speaker 1: things that it uses to help it move around, and
Speaker 1: they kind of like it makes it look like they've
Speaker 1: got a little bit of hair on top of their head,
Speaker 1: like they've got like a sort of wavy mustache that
Speaker 1: comes down.
Speaker 3: No, no seeing it now, there's no charisma to this thing.
Speaker 1: Now, Oh, you are one hundred percent wrong. The number
Speaker 1: of my friends who have jewelry with giardia on it
Speaker 1: is wow. Is there's a lot of us.
Speaker 3: This thing which causes human suffering and death, you guys
Speaker 3: are celebrating and elevating to the level of jewelry. Cool.
Speaker 1: All right, let's talk about let's talk about death. So,
Speaker 1: for all of the parasites that we're talking about today,
Speaker 1: if you are immunal competent, so you're not having immune
Speaker 1: system issues, so you don't have HIV AIDS, you haven't
Speaker 1: recently had an oregon transplant, you know, there's a long list.
Speaker 1: You're not being treated for cancer or anything like that.
Speaker 1: Most of these parasites aren't going to kill you, and
Speaker 1: there's treatments for them, and you will feel unpleasant, but
Speaker 1: especially if you're in a developed country, we can get
Speaker 1: it under control. The folks. Where we need to worry
Speaker 1: are people who are immuno compromised, and in some cases
Speaker 1: we don't have good medications to help people who are
Speaker 1: immunal compromised when they get infected by these parasites. And so, yes,
Speaker 1: I know, every time we talk about parasites, you sort
Speaker 1: of squashed my enthusiasm for the topic by talking about
Speaker 1: all the people who are suffering. I care about the
Speaker 1: people who are suffering, but I can also have immense
Speaker 1: respect for parasites that managed to eke out a living
Speaker 1: in such a like complex and efficient way.
Speaker 3: I mean, I think it's fair. You asked me if
Speaker 3: I worry about the suffering of protons at the.
Speaker 1: Large, and you said no, and then we moved on,
Speaker 1: and then you said you've killed billions of them probably
Speaker 1: that have been around for billions of years, and you
Speaker 1: ended what could have been an infinite lifespan.
Speaker 3: That's true, yes, but protons don't call the diarrhea Kelly. Oh,
Speaker 3: all right, I guess you know protons assembled in the
Speaker 3: form of giardia.
Speaker 1: Do so, that's right, yeah, right, right, Your protons cause suffering.
Speaker 3: Interesting philosophical question there. Who's to blame really for the diarrhea.
Speaker 1: That's right. Okay, let's try to get one more parasite
Speaker 1: in before our break.
Speaker 3: Yeah.
Speaker 1: So the next one is a parasite called Endemyba histolytica.
Speaker 1: So this one is one of the nastier ones. It
Speaker 1: infects about fifty million people worldwide, and about twenty five
Speaker 1: thousand to one hundred thousand deaths are attributed to this
Speaker 1: parasite annually. Yeah, this is not cool. One of the
Speaker 1: reasons it's really hard to study this particular parasite is
Speaker 1: that there are other organisms in our gut that look
Speaker 1: almost exactly the same and they are very closely related.
Speaker 1: And so for a long time, people had trouble identifying
Speaker 1: this as a cause of diarrhea because they'd be like, well,
Speaker 1: we see this when people have diarrhea, we also see
Speaker 1: this when people don't have diarrhea. And it took a
Speaker 1: while to figure out that they were looking at different organisms.
Speaker 3: So that means there are other amiba in our guts
Speaker 3: that don't cause diarrhea. Yep, wow. Yeah, I mean I
Speaker 3: knew there were microbes living within us. I don't think
Speaker 3: I knew that they were like amiba, just like happily
Speaker 3: hanging out. Yeah, Wow, we do contain multitudes, don't we.
Speaker 1: We sure do. Yeah, we should bring Katrina on to
Speaker 1: see what she knows about gut amiba. But anyway, so
Speaker 1: there's a I came across this interesting story that was
Speaker 1: mentioned in a couple different places. I haven't been able
Speaker 1: to trace it to the source yet, but I'm excited
Speaker 1: about it, so I'm going to share it anyway. Apparently
Speaker 1: there's a guy named Fritz Shauden who was interested in
Speaker 1: trying to figure out the difference between the amiba that
Speaker 1: cause disease and the amiba that don't. Yeah, and so
Speaker 1: it sounds like he purposefully infected himself with the ones
Speaker 1: that cause disease to prove it your favorite thing, my
Speaker 1: favorite thing. But one of the problems with this parasite
Speaker 1: is that so it goes into your into it tends
Speaker 1: to live in like the mucus that lines your intestine.
Speaker 1: But every once in a while it will start like
Speaker 1: essentially burrowing deeper and causing pathology like along year intestine,
Speaker 1: or it will escape from your intestine entirely and go
Speaker 1: through your blood to different parts of the body. And
Speaker 1: this is how it ends up killing people. And so
Speaker 1: this poor guy Fritz he ended up getting a particularly
Speaker 1: bad case and died during a surgery to try to
Speaker 1: deal with the complications from having it. But I think
Speaker 1: he showed pretty well that one of them is pathogenic
Speaker 1: and one of them is not. So anyway, this is
Speaker 1: definitely one of those where if you get it, you
Speaker 1: want to take medications to get rid of it, and
Speaker 1: we have amebasides to get rid of it. A mee besides, wow,
Speaker 1: me besides, that's weird.
Speaker 3: Why does one of them cause these complications and other amibi?
Speaker 1: Don't we don't know.
Speaker 3: We don't know.
Speaker 1: No, I don't think we know. Yeah, Nope, I don't
Speaker 1: think we know.
Speaker 3: So Fritz Shouden gave his life in vain.
Speaker 1: No. No, I think it's important to know that there
Speaker 1: are some that cause disease and there are some that
Speaker 1: are discommensals. Because now like you can more easily diagnose somebody,
Speaker 1: and there's a lot of different causes of diarrhea, right,
Speaker 1: and so if you see this amiba, or if you
Speaker 1: see amba in the feces, you say to yourself, I've
Speaker 1: got to figure out if this is the bad amiba
Speaker 1: or if they just happen to have some of the
Speaker 1: okay amiba, because if they've got the bad amiba, there's
Speaker 1: a bunch of additional complications I have to worry about
Speaker 1: in case this thing gets into their blood. And so
Speaker 1: now you like treat more aggressively. And a lot of
Speaker 1: people are thought to have irritable bellel syndrome when they
Speaker 1: actually have this parasite. Not like all of them, it's
Speaker 1: just this happens from time to time, and so you know,
Speaker 1: I think it's important to know that this is a
Speaker 1: thing that can cause disease that kind of looks like
Speaker 1: irritable bell and you need to check into it in
Speaker 1: more detail.
Speaker 3: Yeah, all right, that's true. Okay, So we've done two
Speaker 3: parasites so far, Giardia and these amba. If you had
Speaker 3: to be infected by one of them, which would you.
Speaker 1: Choose giardia out of all the ones? No way, man,
Speaker 1: I would not want ntamba hystalytica. Like if this thing
Speaker 1: the complications from this one are particularly nasty, this is
Speaker 1: one you want to avoid. Wow, But there's two more
Speaker 1: we get to talk about, and so let's take a
Speaker 1: break and when we get back, we will talk about
Speaker 1: two more parasites that actually live inside of the cells.
Speaker 1: And you're intestine.
Speaker 3: Oh boy, okay, we're back and we are inducing nightmares.
Speaker 3: You know. I had a friend email me about our
Speaker 3: recent rat lungworm episode and they were like, look, I
Speaker 3: came for the physics and I like the biology, but
Speaker 3: two parasitologists on the show at the same time is
Speaker 3: a little crazy.
Speaker 1: Oh no, was it too much for them? This sounds
Speaker 1: like it was actually a negative email. I've gotten a
Speaker 1: lot of nice feedback my people, like, no.
Speaker 3: It was positive, but I think it was an intense
Speaker 3: experience for a lot of people. Yeah, that episode as
Speaker 3: it was for me.
Speaker 1: And well yeah, well, and you know, so to be honest,
Speaker 1: when we do one of these intense episodes, I sit
Speaker 1: back and I think why are we doing this to people?
Speaker 1: And I think there's good reason, Like you know, so, yeah,
Speaker 1: I think you need to know how bad rat lungworm
Speaker 1: is so that you can, you know, one, pay attention
Speaker 1: to if it is coming to your area, and two
Speaker 1: decide what kinds of risks you're willing to take with
Speaker 1: your food or know that you need to be managing
Speaker 1: your salads a little bit more carefully. Like I think
Speaker 1: these are things that are important to know about and
Speaker 1: tiptoeing around them might give you a false sense of
Speaker 1: security or like, I don't know. It was a chance
Speaker 1: to put something that I think is important on people's radar,
Speaker 1: even though it is real nasty.
Speaker 3: Totally agree, it's important that we know this stuff, especially
Speaker 3: if it's nasty and it's dangerous, but also totally valid
Speaker 3: response to say, wow, that was gross and hard to
Speaker 3: listen to.
Speaker 1: Yep, yep, yep. Yes. Well, and you know, if there's
Speaker 1: anything in particular, like a moment where it went too far,
Speaker 1: you all can let me know, and Daniel and Matt
Speaker 1: know that they can censor me when needed, and so
Speaker 1: I try to not go too deep into the gross stuff.
Speaker 3: No, this podcast is all about the joy of knowledge,
Speaker 3: and so people want to know. I mean, a lot
Speaker 3: of people wrote in wanted to hear about this, so
Speaker 3: let's give it to them.
Speaker 1: All right, here it's here's some more. Here's some more
Speaker 1: knowledge for your brains. So, crypto spooridiosis is caused by
Speaker 1: a couple of different kinds of cryptosporidium parasites.
Speaker 3: Why is it called crypto? I mean, this has nothing
Speaker 3: to do with like investing in meme coins.
Speaker 1: This came before meme coins bro the meme coins are
Speaker 1: trying to be like cryptosporidium.
Speaker 3: Oh okay, why is it called crypto? Though that crypto
Speaker 3: usually means like hidden or secret, you know, like cryptozoology
Speaker 3: is like study of Bigfoot and lockness, monster and stuff.
Speaker 3: So what's crypto about?
Speaker 1: Cryptosper I am going to guess on the record here.
Speaker 1: I don't actually know the answer. But there are parts
Speaker 1: of your stomach that are called cryps. Oh, and I
Speaker 1: am guessing that they are doing something in those little crips,
Speaker 1: which are sort of like pretty deep inside of like
Speaker 1: the wall of your intestine.
Speaker 3: Oh, I see crypto like crypt keeper nice all right?
Speaker 1: Yeah, yeah, I named a parasite the crypt keeper wasp.
Speaker 1: So anyway, which we talked about with Scott Egan.
Speaker 3: So how common is this one?
Speaker 1: About eight hundred thousand cases in the US. It's the
Speaker 1: second most common cause of diarrhea in kids. So you
Speaker 1: were asking earlier, you know, of the what ten thousand
Speaker 1: pools of feces? And also you're like, Kelly, you're a
Speaker 1: gross How many Olympic swimming pools well of poop are
Speaker 1: we talking about? Kelly? And so maybe you egged me on.
Speaker 3: Yeah, I think that's my role here.
Speaker 1: Yeah, yeah, all right, So a significant portion of those
Speaker 1: pools are probably filled by crypto unfortunately. Wow, and crypto
Speaker 1: differs a bit from some of the other parasites we've
Speaker 1: been talking about, and that it tends to also be
Speaker 1: a problem for a lot of other animals like cattle.
Speaker 1: So there are farms where if the calves get this parasite,
Speaker 1: they're going you know, maybe they'll die, but they also
Speaker 1: grow less well, so it's a problem for productivity. And
Speaker 1: Kay who was one of the listeners who asked for
Speaker 1: like this episode, I think this is what she was
Speaker 1: referring to at the top of the episode, where she
Speaker 1: was talking about how managing the massive quantities of manure
Speaker 1: that are produced on cattle farms is like an important
Speaker 1: public health problem. So you really need to make sure
Speaker 1: that cattle manure doesn't get washed into waterways because otherwise
Speaker 1: you might end up getting this parasite. And so this
Speaker 1: parasite just like the others, you know, it's a poop
Speaker 1: to mouth parasite if you accidentally ingest the cysts that
Speaker 1: were excreted in feces. What this parasite does that's kind
Speaker 1: of interesting is it sticks to the surface of the
Speaker 1: cells that line you're intestine, and then the micro those
Speaker 1: villi that we were talking about, they get longer and
Speaker 1: they fuse around it, and so now they make like
Speaker 1: a little intracellular space. And I don't know if, like
Speaker 1: in some cases, that's a good strategy for walling off
Speaker 1: parasites so they don't cause more problems, and it just
Speaker 1: doesn't work in this case, or if this is a
Speaker 1: situation where the parasite is manipulating the vli into making
Speaker 1: a little home for it. I don't think we know
Speaker 1: the answer. But now it's intracellular and it starts replicating
Speaker 1: inside of those cells, and when it's done, it bursts
Speaker 1: those cells open and goes off in search of new cells.
Speaker 1: And your immune system responds to all of that. And
Speaker 1: so this is a situation where probably some combination of
Speaker 1: like physical damage that is happening to your intestine because
Speaker 1: of the parasite and your immune system responding strongly to
Speaker 1: that might be what induces diarrhea. Interesting, and the same
Speaker 1: thing happens with cyclospora is also an intracellular parasite. I
Speaker 1: think the mechanisms are a little different, but the idea
Speaker 1: there is the same that you're inside of the cells,
Speaker 1: you burst those cells open from time to time and
Speaker 1: the immune system response. You're definitely messing stuff up in
Speaker 1: your intestine.
Speaker 3: And you mentioned here that UV light is a powerful
Speaker 3: way to kill this parasite. Why don't we use UV
Speaker 3: light on all of our food?
Speaker 1: So I think the answer to that is if you
Speaker 1: were to buy, like, what is it a head or
Speaker 1: a heart of romaine lettuce? Why do we name them
Speaker 1: after body parts? It's a plant, I don't know, should be.
Speaker 3: Called a knee of romain lettuce, that's.
Speaker 1: Right, that's I think a foot something. So if you
Speaker 1: get out your foot of romaine lettuce and you go
Speaker 1: to pass it under a UV light, there's a lot
Speaker 1: of like crinkles and areas that probably won't get hit
Speaker 1: by that UV light. And if you've got something like
Speaker 1: you know, romain lettuce where multiple leaves are stuck together
Speaker 1: van you know there's going to be areas that don't
Speaker 1: get hit by that UV light, and you'd have to
Speaker 1: worry about, like I guess, either rotating it or getting
Speaker 1: it on both sides as it goes through. This just
Speaker 1: seems to me like a method that could convince you
Speaker 1: that you've done a good job of cleaning your food,
Speaker 1: but it would be very easy to miss areas with
Speaker 1: the UV light, just because it's not like a sheet
Speaker 1: where it's easy to get.
Speaker 3: It all interesting. I know that UV light passes through
Speaker 3: water fairly easily, like you can get a sunburn even
Speaker 3: if you're underwater. But I think the outer layers of
Speaker 3: lettuce cells will not let you be through. So you're
Speaker 3: right that like the inner layers won't. But more broadly,
Speaker 3: why don't we use radiation? I think our listener recently
Speaker 3: wrote in and asked about why we don't use radiation
Speaker 3: more often to make our food safe.
Speaker 2: Yeah.
Speaker 1: I don't know the answer. My guess would be again
Speaker 1: that it's hard to make sure you got everything. Do
Speaker 1: you think the radiation could like damage the plant cells
Speaker 1: in some way that would make the food less tasty?
Speaker 1: I don't know.
Speaker 3: Perhaps my guess with that doing a lot of research,
Speaker 3: is that radiation sounds yucky to people and they don't
Speaker 3: want to eat food that's been irradiated because maybe it's
Speaker 3: going to make them have a third eyeball or poop
Speaker 3: green slime or something like that. You know, since Three
Speaker 3: Mile Island radiation it's pretty bad rap.
Speaker 1: Yeah, unfortunately. But another thing that's tough about this parasite
Speaker 1: is that chlorine doesn't do a great job of killing it.
Speaker 1: And so this is one of the reasons where if
Speaker 1: a kid poops in the pool, everybody's got to go
Speaker 1: out because just a little bit of chlorine. Bumping up
Speaker 1: the chlorine just a little bit isn't going to do
Speaker 1: the trick. So, like, as I understand it, if a
Speaker 1: kid is wearing a diaper and they do a solid
Speaker 1: turd in their diaper, everybody has to get out and
Speaker 1: they bump up the chlorine a little bit and they
Speaker 1: call it a day. But if someone has diarrhea and
Speaker 1: you're worried about crypto, everybody has to get out and
Speaker 1: they bump the chlorine up massively and people have to
Speaker 1: stay out because the chlorine levels are like, you know,
Speaker 1: burn your skin level high and you have to wait
Speaker 1: until the levels go back down again. And so that's
Speaker 1: why diarrhea can shut down a pool.
Speaker 3: How the levels go back down, you just got to
Speaker 3: add fresh water.
Speaker 1: I think the chlorine evaporates off over time.
Speaker 3: Oh no, actually I think the radiation breaks down the chlorine.
Speaker 3: Oh okay, the sun's radiation. Yeah.
Speaker 1: Yeah, all I know is I need to keep adding
Speaker 1: chlorine to my pool. It's not building up over time.
Speaker 1: But yeah, So, crypto in particular is a parasite that
Speaker 1: we worry about in pools, and it's not cool that
Speaker 1: it's so hard to kill it with chlorine. And so
Speaker 1: finally we get to cyclosporiasis, which is what we are
Speaker 1: all concerned about today.
Speaker 3: The newly famous parasite.
Speaker 1: The newly famous parasite. One of the things that's interesting
Speaker 1: about this parasite is that it was a thing that
Speaker 1: we weren't super worried about from a public health perspective
Speaker 1: in the United States for a while. But in recent
Speaker 1: years we've been seeing more and more outbreaks caused by
Speaker 1: this parasite. We don't exactly know why, maybe something about
Speaker 1: changes in temperatures or making it so that the cysts
Speaker 1: can survive in the environment for longer.
Speaker 3: Daniel eating so many backslids.
Speaker 1: Daniel in particular is the source of cyclo for everybody. Uh,
Speaker 1: he's got to stop pooping in the lakes and in
Speaker 1: the pools down the raspberry.
Speaker 3: Wow, you just took a little joke and went way
Speaker 3: too far with it.
Speaker 1: I feel like that's usually your job, but sometimes.
Speaker 3: All right, well, I'm going to take heart in the
Speaker 3: fact that you're not mad at the beavers for pooping
Speaker 3: in the water, and so.
Speaker 1: You know better, man, you know better. I know where
Speaker 1: you're going with this, you know better, right, all right? So, anyway,
Speaker 1: we're seeing more outbreaks. Part of this could be because
Speaker 1: we're better at detecting it in the environment. So like
Speaker 1: for a long time we didn't even have the genome
Speaker 1: of this parasite so that we could do proper tracing.
Speaker 1: But we've got the genome. Now, we have more tools,
Speaker 1: and if we would just stop firing the people who
Speaker 1: use these tools, we might be in a better position.
Speaker 1: But anyway, so this is something that's more often a
Speaker 1: problem in Canada, Poland, the United Kingdom, the United States
Speaker 1: than we've seen in the past.
Speaker 3: And it's the basic story the same. You're eating the
Speaker 3: cyst and then it latches on somewhere inside you and
Speaker 3: it grows and makes more cysts, and for reasons we
Speaker 3: don't understand, induces diarrhea and the cysts come out in
Speaker 3: your diarrhea.
Speaker 1: Yes, So one thing that's sort of interesting and a
Speaker 1: little bit different about this parasite is you know, for
Speaker 1: all of the parasite, it takes about a week for
Speaker 1: I'm guessing the damage to your intestines to build up
Speaker 1: and then you start having diarrhea. But a lot of
Speaker 1: the parasites, once the parasite gets into the environment again,
Speaker 1: it's ready to infect the next host. This parasite needs
Speaker 1: something like a week depending on temperature. We haven't really
Speaker 1: been able to study this in the wild very well,
Speaker 1: but it needs a little while to mature in the environment.
Speaker 1: And so this means that you don't often get cyclospora
Speaker 1: passing from you know, for example, somebody at a daycare
Speaker 1: center changing a kid's diaper and like passing to the
Speaker 1: other kids if hands don't get washed because you've got
Speaker 1: like a week to disinfect all of your surfaces. So
Speaker 1: it doesn't usually go from person to person. But if
Speaker 1: it's in the produce and then it gets shipped around
Speaker 1: the country, it takes about a week for that to happen.
Speaker 1: Now the parasite is ready to infect people, and then
Speaker 1: it takes another week for symptoms to show up.
Speaker 3: And lots of parasite stories we've heard on this podcast
Speaker 3: involve like hilarious different situations like it comes out of
Speaker 3: this creature and then it's got to go up the
Speaker 3: nose of that one, and then it have to be
Speaker 3: on the hairs of this guy. Whereas cyclo seems to
Speaker 3: only grow in the guts of humans. Why isn't there
Speaker 3: some Rube Goldberg complicated life story here.
Speaker 1: I mean, I feel like it's still pretty complicated. It
Speaker 1: needs to be out in the environment for like a
Speaker 1: week and then it can get into people. But some
Speaker 1: of the other parasites that we've been talking about, some
Speaker 1: of it is complicated. Well, so what makes Geordia, for example,
Speaker 1: more complicated. It seems to me that it's less complicated
Speaker 1: that it can live in a beaver, it can live
Speaker 1: in a human. It's come up with like a more
Speaker 1: generalist way of doing things, whereas cyclo is like pretty specific.
Speaker 1: You know, it needs to get into a human. We
Speaker 1: think there have been some studies suggesting maybe it can
Speaker 1: live in a couple other animals. This is like an
Speaker 1: active area of research. But Cyclospora is one of the
Speaker 1: more human specific pathogens that we've talked about, like crypto Sporidium.
Speaker 1: There's a lot of different species that affect a lot
Speaker 1: of different animals, and some of them can also infect humans,
Speaker 1: but cyclo is pretty specific.
Speaker 3: All right, So I think what a lot of people
Speaker 3: want to know is, Kelly, you're a parasitologist. We're reading
Speaker 3: a lot of stuff on the news. Nobody really knows
Speaker 3: what's going on. What should we do? Should we eat
Speaker 3: bagged salad? Should we only eat canned food and heat
Speaker 3: it up to one hundred and seventy degrees? Tell us
Speaker 3: how to stay safe? Kelly?
Speaker 1: All right, So, first of all, if you are a
Speaker 1: person who's immunal compromise, you need to be extra careful. Unfortunately, Yeah,
Speaker 1: people can make a decision about for themselves about whether
Speaker 1: or not, you know, they're feeling comfortable eating bag salads.
Speaker 1: At this point where we don't feel like we've wrapped
Speaker 1: up all of the details about the current outbreak, I
Speaker 1: am personally rinsing and hoping it's okay, because I feel
Speaker 1: like the benefits of salad for me outweigh the risks
Speaker 1: when it looks like we've already identified tailor farms as
Speaker 1: the source. So I'm okay with eating some other salads.
Speaker 1: But if I was im mutal compromise, or my kid was,
Speaker 1: I might make a totally different decision. And so what
Speaker 1: I can suggest is that websites like the CDC and
Speaker 1: the Food and Drug Administration and the World Health Organization,
Speaker 1: all of those websites have advice for how to keep
Speaker 1: yourself safe, and you should definitely listen to those instead
Speaker 1: of listening to Kelly. But here are some things that
Speaker 1: they are going to tell you. They're going to tell
Speaker 1: you that you should wash your hands regularly, especially before
Speaker 1: you go to eat, and especially if you've been touching livestock,
Speaker 1: if you've been at a petting zoo, or if you've
Speaker 1: been changing diapers, you should really carefully wash your hands
Speaker 1: and sanitize any surfaces that you've touched. Do not swallow
Speaker 1: water at public pools. I'm looking at you, son of mine.
Speaker 1: You need to stop doing that. Don't drink water from pools, rivers, lakes, etc.
Speaker 1: Unless you have treated it so. There are certain kinds
Speaker 1: of filters you can buy, and there are tips for
Speaker 1: how long you need to boil water to make sure
Speaker 1: that you've killed these things. If you are going hiking
Speaker 1: or you think the apocalypse is coming, you should read
Speaker 1: up on what to do if you are going to
Speaker 1: be drinking water that hasn't been properly sanitized beforehand. You
Speaker 1: should support programs that make sure livestock waste can't get
Speaker 1: into your waterways. You should be a little concerned that
Speaker 1: we're firing some of the people who track this stuff down.
Speaker 1: Those people have important jobs and they need help. Be
Speaker 1: a little bit cognizant when you're being intimate with your
Speaker 1: partner about whether you might have come in contact with FECs.
Speaker 1: If you've had diarrhea recently, give it a break for
Speaker 1: a week, and you know, try to make sure you're
Speaker 1: not passing anything to your partners. If you go to
Speaker 1: an area where these parasites are much more common, keep
Speaker 1: in mind that people who live in these areas are
Speaker 1: more likely to be asymptomatic than the rest of us.
Speaker 1: It could be because throughout their lives they've been exposed
Speaker 1: to this parasite at a low level and their immune
Speaker 1: systems are better able to handle it. But a lot
Speaker 1: of time, if someone from a developed country goes to
Speaker 1: a less developed country where the parasite is common, even
Speaker 1: if everyone else is drinking the tap water and putting
Speaker 1: the ice in their drinks and they're fine, you might
Speaker 1: not be. And so if you go to one of
Speaker 1: these areas, you should drink bottled water, you shouldn't put
Speaker 1: ice in that water, and you should maybe only eat
Speaker 1: foods that have been cooked well. So keep in mind
Speaker 1: that raw fruits and vegetables that have been rinsed in
Speaker 1: tapwater might have the parasite on it. So if you're
Speaker 1: gonna eat fruits, you know, if you want a banana
Speaker 1: or something, maybe you should go ahead and peel that
Speaker 1: banana because the inside probably isn't infected with something, but
Speaker 1: there could be some parasites on the outside. Yeah, and
Speaker 1: before you travel, you should always check websites like the
Speaker 1: CDC and the World Health Organization to see what their
Speaker 1: advice is for when you go to one of those places.
Speaker 1: So there are ways to keep yourself safe, and one
Speaker 1: of those ways is by supporting the people whose job
Speaker 1: it is to try to make sure that you stay safe.
Speaker 3: That sounds like solid advice, all right, So give us
Speaker 3: Kelly's predictions for the future. Do you think we are
Speaker 3: facing every year bigger and bigger outbreaks of these parasites
Speaker 3: or do you think we're going to figure it out
Speaker 3: and get it under control, or what does the world
Speaker 3: look like for our.
Speaker 1: Kids Kelly, if you were to draw a trend line
Speaker 1: for cyclospora in the United States, I think you would
Speaker 1: see cases increasing over time. I don't think that we
Speaker 1: are powerless in the face of that trend. I think
Speaker 1: that we could amp up our surveillance and be more
Speaker 1: careful both at like the company level, and at the
Speaker 1: level of reporting when people start getting diarrhea, figuring out
Speaker 1: what it is in reporting that kind of stuff. So,
Speaker 1: you know, I never like to be negative. I like
Speaker 1: to be gross, but not negative. So there are things
Speaker 1: we can do, and so I'm going to hope that
Speaker 1: we do those things.
Speaker 3: All right, Well, I think it's always better to know.
Speaker 3: So thank you for taking us on this sometimes uncomfortable
Speaker 3: but very educational journey.
Speaker 2: Yeah.
Speaker 1: I hope none of you have gotten cyclistpora. And wash
Speaker 1: your hands.
Speaker 3: Stay clean, and stay safe everybody. Thanks everybody for listening.
Speaker 3: Please go and do us a favor and rate the
Speaker 3: show on whatever podcast app you're using. It really helps
Speaker 3: people find us.
Speaker 1: Daniel and Kelly's Extraordinary Universe is edited by the amazing
Speaker 1: Matt Kesselman.
Speaker 3: He really is a wizard. You can also find us
Speaker 3: online on Blue Sky, Instagram, and x D and K universe,
Speaker 3: come engage with us.
Speaker 1: You can email us at questions at Danielankelly dot org.
Speaker 1: We really do want to hear.
Speaker 3: From you, and you can find our website www dot
Speaker 3: danieland Kelly dot org, where you'll also find an invitation
Speaker 3: to join our discord where everybody comes and talks about
Speaker 3: the amazing universe.
Speaker 1: And we also have the most amazing moderators. This is
Speaker 1: an iHeart podcast. Thanks for joining us.