Speaker 1: By US standards, Brazil's Highway BR fourteen is certainly no
Speaker 1: Indiana Turnpike or New York State Thruway. Meandering one three
Speaker 1: hundred and fifty miles from Belem to Brasilia through the
Speaker 1: jungles and scrub of Brazil's wild interior, it is barely
Speaker 1: two lanes wide. The surface is dust in the dry season,
Speaker 1: mud in the wet and some of the ruts could
Speaker 1: swallow a Volkswagen alive. Yet, in the eyes of former
Speaker 1: President Juicellino Kubacek, who built the road between nineteen fifty
Speaker 1: six and nineteen sixty, BR fourteen is the highway of
Speaker 1: dreams for underdeveloped Brazil and the means to a new
Speaker 1: civilization on the central plateau. So it is since the
Speaker 1: road's opening in nineteen sixty, some six hundred thousand settlers
Speaker 1: have poured into the area to tap Brazil's immense riches.
Speaker 1: Every day, long lines of trucks rumble north and south,
Speaker 1: carrying out lumber, rubber, and vegetable oil. New farmlands produce beans, rice, corn,
Speaker 1: and fruit to feed Brazil's exploding population. What was once
Speaker 1: useless scrub in the central state of Goyas is now
Speaker 1: pastureland for four million head of cattle, and prospectors fanning
Speaker 1: out from the road have found a vast mineral potential,
Speaker 1: with deposits of nickel, tin, lead, zinc, copper, gold, diamonds,
Speaker 1: and quartz. Towns are sprouting every few miles. If I
Speaker 1: don't pass a certain stretch of road for two or
Speaker 1: three weeks, says one road engineer, I almost always find
Speaker 1: a new cluster of shacks there when I get back.
Speaker 1: Our Guayina, which got its start in nineteen fifty eight
Speaker 1: as a road construction camp five hundred miles north of Brasilia,
Speaker 1: is now up to eight thousand people, has its own
Speaker 1: branch of the Bank of Brazil, and will soon have
Speaker 1: a one point six million dollar factory that will refine
Speaker 1: oil from native babecue, nuts, peanuts, cotton, and sunflower seeds,
Speaker 1: and produce the cans in which to export the oil
Speaker 1: and cut up local mahogany to make cases for the cans.
Speaker 2: I love your newscaster voice, thank you, and I hate
Speaker 2: everything else about that.
Speaker 1: I think it so. That was from excerpted from a
Speaker 1: Time article published on January seventh, nineteen sixty six, titled
Speaker 1: Brazil on the Road. To dreams, and it's such a
Speaker 1: fascinating reflection. I think of how forward progress was viewed
Speaker 1: at the time, like yeah, we must go forward, and
Speaker 1: like it's it's also understandable, right right, Like there's this
Speaker 1: is economy that's driving this. But the reason that we
Speaker 1: picked this particular article or this excerpt is because that
Speaker 1: construction on that road is what is thought to have
Speaker 1: led to the spillover and spread initially of the focus
Speaker 1: of today's episode, which is or a pouch virus. Hi,
Speaker 1: I'm Aaron Welsh and I'm Erin Alman Updike, and this
Speaker 1: is this podcast, will kill you? Welcome to or a
Speaker 1: push virus? Or a push virus. Yeah, we've got one
Speaker 1: time to learn how to say that. Yeah, this morning.
Speaker 1: We've gotten some requests over the years for this virus,
Speaker 1: and it's interesting. I feel like we've been seeing it
Speaker 1: trickle more and more in the news lately, and so
Speaker 1: we wanted to just kind of like get a lay
Speaker 1: of the land. What's going on, how is it transmitted?
Speaker 1: Why is it suddenly making headlines.
Speaker 2: It's it's gonna be a great episode because I feel
Speaker 2: like it's really going back to urine my roots. Erin
Speaker 2: of like, what got us wanting to make this podcast
Speaker 2: in the first place. And it's been a really long
Speaker 2: time since we've done a vector worn disease, since we've
Speaker 2: done an infectious disease.
Speaker 1: So I was like, how do we do this? I
Speaker 1: know there aren't many books to read on this right.
Speaker 2: Yeah, So yeah, We've got a lot for this episode
Speaker 2: and I'm excited about it.
Speaker 1: Me too, Me too. What are we drinking this week, Aaron?
Speaker 1: We're drinking sloth sprits. Yeah, or push virus is often
Speaker 1: called sloth fever or sloth flu. Been seen it called,
Speaker 1: and I don't love it, no, but we are going
Speaker 1: to honor the sloth in this way. I love sloths.
Speaker 1: I do too, I do too. Yeah, tell us what's
Speaker 1: in sloth sprits?
Speaker 2: You know, it's a delicious little concoction of passion fruit
Speaker 2: juice or whatever, nectar nectar, passion fruit, lime, mint, and
Speaker 2: you know, some bubbly of some kind.
Speaker 1: Choice's delicious, refreshing, et cetera. All the above. We'll post
Speaker 1: it on our socials. In our socials, on our socials,
Speaker 1: not our website.
Speaker 2: But on our website you can find a lot of
Speaker 2: other great stuff, like, for example, transcripts from all of
Speaker 2: our episode sources from this in every single episode, Bloodmobile.
Speaker 2: Who does the music? We've got merch This is an
Speaker 2: old one. I don't know if it's still available.
Speaker 1: I love that shirt though, met too.
Speaker 2: We've got Patreon, We've got a contact us form, a
Speaker 2: first hand account form.
Speaker 1: Listen, it's basing than Look. Yeah, this podcast will kill
Speaker 1: you dot com. It's there, It's there. I have a
Speaker 1: piece of business because this has been bothering me since
Speaker 1: we listened to the episode for like QC purposes. You
Speaker 1: know what I'm gonna say, erin I do elephant I didn't.
Speaker 1: This has bothered me deeply that I mess this up.
Speaker 1: Elephant's poop. If I had thought about it, I would have.
Speaker 1: I would have. I would have realized that fifteen pounds
Speaker 1: sounds like a lot to us, but for an elephant,
Speaker 1: which is gargantuan, right, actually doesn't sound like that much
Speaker 1: in a day. And it's true, it's not that much
Speaker 1: for an elephant in a day. Fifteen pounds is more
Speaker 1: like in one poop sash throughout the day. It's about
Speaker 1: two hundred and twenty pounds. That's pounds, and they poop
Speaker 1: like twelve to fifteen times a day. So that's how
Speaker 1: the wow maths. Yeah, twelve to fifteen times a day.
Speaker 1: They're basically it's just they're just poopish. Yeah, the constant wow.
Speaker 2: I love knowing that fat for more poop facts. What's
Speaker 2: really funny, Aaron is in that episode when you say
Speaker 2: fifteen pounds, I'm like, fifty pounds because I also clearly
Speaker 2: was like that sounds like so much. I numbers are
Speaker 2: really hard to conceptualize sometimes.
Speaker 1: I mean, when you're talking about pounds of poop, it
Speaker 1: really does feel Yeah. Yeah, So anyways, anyways, that's my correction. Oh,
Speaker 1: I just wanted to mention this is technically the start
Speaker 1: of season nine. I know, there's no break, and so
Speaker 1: if we if you hear AU say season nine or
Speaker 1: new season or whatever, it's only for at this point
Speaker 1: our file, organizational system, our file.
Speaker 2: But and also like I think, our hearts because I'm
Speaker 2: really proud that we've made it to season nine.
Speaker 1: Are you hitting me? Yeah? We doing this for that long? Yeah,
Speaker 1: Halloween twenty seventeen. Yeah, we're still there's still more things
Speaker 1: that can kill you.
Speaker 2: So speaking of a whole season planned, but first we
Speaker 2: begin with or a poosh virus right after this break
Speaker 2: or a pooshe virus is an arbovirus, which means that
Speaker 2: it's a virus that is transmitted by arthropods, an arthropod
Speaker 2: born virus. Some of our favorites that we've ever covered,
Speaker 2: I think are arboviruses vector born diseases in general.
Speaker 1: I mean disease ecology really, you know, Yeah, it's in
Speaker 1: our heart of hearts. True.
Speaker 2: But one of the things that's quite unique about this
Speaker 2: virus compared to any other that we have covered before,
Speaker 2: is that it's transmitted by a whole new arthropod that
Speaker 2: we have never talked about on this podcast, and that.
Speaker 1: Is a midge. A midge, So let's talk about what
Speaker 1: image is, shall we. Yeah, I am, I can't I
Speaker 1: truly can't wait. I mean that sincerely.
Speaker 2: So a midge or a biting midge is a type
Speaker 2: of biting fly, And the term biting midge is not
Speaker 2: a very scientific grouping of biting fly whatsoever, because in
Speaker 2: some places these might be called sandflies, even though they
Speaker 2: might not be what we would have called sand flies.
Speaker 2: In other places, they might be called no sums. And
Speaker 2: there's probably even more other terms that people use for these,
Speaker 2: but in any case, these are teeny tiny, and by
Speaker 2: teeny tiny, I mean they're like one to three millimeters long.
Speaker 2: Like the there's pictures of them online on someone's thumbnail
Speaker 2: where they barely take up the space that like between
Speaker 2: your cuticle and your thumb.
Speaker 1: Like barely, Sam, Yeah, no, barely, Sam.
Speaker 2: There's other pictures online of them next to a mosquito,
Speaker 2: and you think of mosquitos, like, they're not very large
Speaker 2: compared to many other types of flies.
Speaker 1: Depending on the mosquito. But yeah, yeah, some of them
Speaker 1: are heaty, scary ones.
Speaker 2: Yeah, right, but they're but compared to a mosquito, they're
Speaker 2: like so deeny.
Speaker 1: They're like the size of a.
Speaker 2: Mosquito's head that is cheni, I know, kind of adorable.
Speaker 2: And in this case, we're talking about these biting midges
Speaker 2: in the family serato Pogona dae, specifically this species. There's
Speaker 2: one major species that we think is the primary vector
Speaker 2: for oropoosch virus, and that is Culaicoid's paraensis. Yes, and
Speaker 2: these biting midges in this family and in this genus,
Speaker 2: they share some similarities with mosquitoes, but also quite a
Speaker 2: lot of differences. First of all, they're quite small. They're
Speaker 2: proboscis that they use to bite us and do their
Speaker 2: blood feeding is not nearly as long or robust as mosquitoes,
Speaker 2: so they can't as easily bite through our clothing.
Speaker 1: Oh that's good news. It is good news.
Speaker 2: However, they're so small that they can fit through things
Speaker 2: like most of our screensh No, yes, yes, so they're
Speaker 2: harder to keep out of your house and things like that. Okay,
Speaker 2: But similar to mosquitoes, their larvae are aquatic, and similar
Speaker 2: to mosquitoes, it is only the females who blood feed
Speaker 2: in order to mature their eggs. So in the case
Speaker 2: of oropush virus, this midge Quliicoid's paraensis will take a
Speaker 2: blood meal from an infected person or animal. We'll get there,
Speaker 2: and then upon their next blood meal, we'll spit that
Speaker 2: virus back out into another host. And that is kind
Speaker 2: of all that I can say about the transmission cycle.
Speaker 2: Sometimes in these virus or arbovirus or vector borne disease episodes,
Speaker 2: we can get into a lot more detail about what's
Speaker 2: going on inside that vector, about how long it takes
Speaker 2: for this virus to disseminate and then be able to
Speaker 2: be transmitted. It is amazing how relatively little we know
Speaker 2: about this virus. So we think that this one species,
Speaker 2: Kuloicoid's paraensis, this one species of biting midge is the
Speaker 2: primary vector to humans and probably to other animals. But
Speaker 2: much like many other vector born diseases that we've covered
Speaker 2: on this podcast, there are kind of two different cycles
Speaker 2: of this virus. Right, there's a wild cycle or a
Speaker 2: sylvatic cycle, and there's an urban cycle. And in the
Speaker 2: wild or silvatic cycle. It's thought that sloths, especially three
Speaker 2: toe sloths as well as I know, right.
Speaker 1: They're like, I'm sorry, but they are the cuter slot,
Speaker 1: but you apologize just like by far. Yeah, it's quite dramatic,
Speaker 1: it is. They're the ones with a mask.
Speaker 2: If you haven't, if you don't distinctly know off the
Speaker 2: top of your head the differences between a two tone
Speaker 2: and in addition to the number of toes, the three
Speaker 2: toes are the ones with the black and white little mask,
Speaker 2: and the two toes are brown and have a little.
Speaker 1: Pig nose, which is also cute, but it is a
Speaker 1: different way, you.
Speaker 2: Know, And I do like how fuzzy like their fur
Speaker 2: is like longer and anyways, this is not an episode
Speaker 2: about slots.
Speaker 1: It should be it could be done.
Speaker 2: So it is thought that sloths, as well as non
Speaker 2: human primates like capuchins and howler monkeys and some bird species,
Speaker 2: these are probably the most important vertebrate hosts of this virus.
Speaker 2: But when it comes to the vector species, we don't
Speaker 2: really know exactly which arthropods, which biting insects are playing
Speaker 2: the biggest role in transmission in this wild cycle.
Speaker 1: Especially so we.
Speaker 2: Know that this biting midge, the Culicoiles paraensis, is definitely
Speaker 2: present in the selvatic cycle. It definitely can and does
Speaker 2: bite freely other animals in addition to humans. But there's
Speaker 2: some evidence that various mosquito species, including some Clex mosquitoes
Speaker 2: which transmit a wide variety of other illnesses, and some
Speaker 2: eighties mosquitoes which are the primary vectors for things like
Speaker 2: dengae virus which circulates in the same area as or
Speaker 2: a pooch virus. Some of these mosquite have been found
Speaker 2: to be infected with or a push virus, but we
Speaker 2: don't really know are they what we call competent vectors,
Speaker 2: can they actually transmit this virus to other animals, and
Speaker 2: like how big of a role do they play in
Speaker 2: the environment. We don't know, which is fascinating.
Speaker 1: Okay, so a question about that, like what is the
Speaker 1: midge's habitat preferences? Great question, We don't really know. We
Speaker 1: don't really know.
Speaker 2: Apparently the larva, especially of these species, this species in particular,
Speaker 2: wasn't even like described and identified until the nineteen nineties,
Speaker 2: which is so recent, and so we really just don't
Speaker 2: know nearly as much as we should about the natural ecology.
Speaker 2: And while other biting midge species are known to be
Speaker 2: important vectors of a variety of animal diseases like blue
Speaker 2: tongue virus and other viral infections as well, I don't
Speaker 2: think that they have historically been considered as imp important
Speaker 2: of a vector of human diseases compared to something like mosquitoes.
Speaker 2: And so that's probably part of why their natural ecology
Speaker 2: and just their understanding as vectors and just in general
Speaker 2: is not as robust as it's just it's.
Speaker 1: Just so interesting because I feel like they they occupy well,
Speaker 1: do they occupy a similar niche as mosquitoes? They yeah,
Speaker 1: But like there's there's like why do midges play less role?
Speaker 1: This is like a bigger question than, but you can
Speaker 1: ask it in general. You know, mosquitoes are what we
Speaker 1: think of when we think of like vector born diseases
Speaker 1: like mosquitoes, ticks and and midges don't feature very heavily.
Speaker 2: Why why great question, I don't know, so yeah, But
Speaker 2: so that's we think though, that this is the main
Speaker 2: vector species. There's one other species of Kuliquoides as well
Speaker 2: that has sometimes been found to be infected that might
Speaker 2: play a role, especially in the urban cycle as well.
Speaker 2: And the urban cycle meaning in the human cycle of.
Speaker 1: Or A push virus.
Speaker 2: It really is us humans who play the primary vertebrate host.
Speaker 2: Our domestic animals do not seem to play a big
Speaker 2: role in the maintenance of this virus in urban cycles,
Speaker 2: except maybe chickens.
Speaker 1: Even then, Yes, we don't study it enough.
Speaker 2: Will know a lot more in the coming years, but
Speaker 2: there is still so much that we don't really know
Speaker 2: about this virus. What we do know is how it
Speaker 2: tends to present. Even though the symptoms of or A
Speaker 2: push virus really overlap with so many other arboviral so
Speaker 2: like vector born viral illnesses and just other viral illnesses
Speaker 2: in general, so they're very nonspecific. The symptoms tend to
Speaker 2: start with a fever.
Speaker 1: Classically.
Speaker 2: Classically, headache is a very very common symptom, as well
Speaker 2: as muscle aches, joint aches, dizziness. You might get chills.
Speaker 2: Oftentimes people will have like ocular symptoms, eye symptoms like photophobia,
Speaker 2: like your eyes hurt if you're trying to look at
Speaker 2: the light. Or sometimes people get like redness in their eyes,
Speaker 2: not like as full on as like a you know,
Speaker 2: red eye, like pink eye infection, but just a bit
Speaker 2: of like redness overall in the eyes.
Speaker 1: Isn't doesn't that happen with zica or chicken guna, It
Speaker 1: can happen with Yeah, I just feel like it was
Speaker 1: like a feature symptom in one of those mosquito born ones.
Speaker 1: That is more than I can remember, Aaron. It could
Speaker 1: be a false memory, that's possible.
Speaker 2: Sometimes people will have some like GI symptoms like nausea, vomiting,
Speaker 2: abdominal pain. Sometimes they might have anorexia, like you just
Speaker 2: feel so sick you don't really want to eat anything.
Speaker 2: Sometimes people can get a rash, and I've seen it
Speaker 2: described as kind of a Rubella type of rash. And Rubella,
Speaker 2: if you don't remember, is another viral illness, not vector
Speaker 2: born that causes this red, splotchy, pinpricky type of rash
Speaker 2: that often is on like the torso and then can
Speaker 2: spread to the face and spread downward. But it's really
Speaker 2: like a very kind of non specific viral looking rash,
Speaker 2: is the way I would describe it. And rarely sometimes
Speaker 2: people can have haemorrhagic symptoms, so that might be things
Speaker 2: that look like you're having a bit of bleeding, but
Speaker 2: not like bleeding everywhere, but maybe your gums or maybe
Speaker 2: a nose bleed or other kind of mucosal type of bleeding.
Speaker 1: How is the virus causing these symptoms?
Speaker 2: Great question, aarin no idea. Okay, we know so little.
Speaker 2: I have a bit on this later on, but i'll
Speaker 2: tell you now erin. We know so little about the
Speaker 2: like pathophysiology of what this virus is doing in our bodies,
Speaker 2: what sells? Is it even infecting? What sells? Does it
Speaker 2: preferentially and effect? And where does it replicate? Like are
Speaker 2: there specific tropisms, meaning are there certain types of cells
Speaker 2: that it preferentially is going to infect and how and
Speaker 2: why those cells?
Speaker 1: And what are these symptoms? We don't know. We don't
Speaker 1: know any of that as far as I can tell.
Speaker 2: Okay, okay, So yeah, we don't know why it's causing
Speaker 2: these very non specific viral type symptoms.
Speaker 1: But it is another thing though.
Speaker 2: That we see with our push virus that we see
Speaker 2: with a lot of other arboviral diseases, is that the
Speaker 2: course of your symptoms can be what we call biphasic,
Speaker 2: meaning that three to ten days or so after you
Speaker 2: get infected, that's the usual incubation period. So after you
Speaker 2: get these bites from these midges and you get infected,
Speaker 2: you start with these symptoms that I've described, and that
Speaker 2: first phase usually lasts like two to four days or so, okay,
Speaker 2: and then you will get better, but then a week
Speaker 2: to ten days later you might have a resurgence of
Speaker 2: very similar symptoms. How often does this happen, we don't
Speaker 2: really know, because again there's so much that we don't know,
Speaker 2: but it suggested that it's like in up to sixty
Speaker 2: percent of cases, which is quite high, so quite common
Speaker 2: that you would have this kind of bi phasic illness.
Speaker 1: And most of the time, I think the.
Speaker 2: Best news about or a push virus is that the
Speaker 2: vast majority of the time this is a self limited disease,
Speaker 2: meaning those symptoms that I describe. You feel miserable, you
Speaker 2: feel sick. Maybe it comes back and it lasts for
Speaker 2: quite a while, but then you get better. When this
Speaker 2: disease causes more severe symptoms, which it can, it can
Speaker 2: result in a meningitis or a meninjo encephalitis, meaning infection
Speaker 2: in the brain brain stem, causing swelling in your central
Speaker 2: nervous system. Even in those cases, people almost always recover
Speaker 2: and recover completely as far as we know, and there
Speaker 2: are asterisks there, but up until twenty twenty four or
Speaker 2: a PUSH virus had not been known to cause any deaths.
Speaker 2: That's no longer true, but we'll talk more about it later, Okay.
Speaker 1: Immunity immunity, great question. We don't know.
Speaker 2: Okay, we don't know how good of immunity we generate.
Speaker 2: Is our antibody immunity like long lasting? Can you get
Speaker 2: reinfected with this?
Speaker 1: We don't know. Are there different strains or like subtypes?
Speaker 2: So there definitely are, Okay, there definitely are. And this
Speaker 2: is actually a really important part of our push biology
Speaker 2: that we do know.
Speaker 1: Quite a bit about. Okay.
Speaker 2: So, similar to flu viruses oropush viruses, are an RNA
Speaker 2: virus that has a segmented genome, which means their genome
Speaker 2: is not just like one piece of RNA, it's three
Speaker 2: different chunks. They're named small, medium, in large, SM, and
Speaker 2: L and similar to flu viruses, if a host like
Speaker 2: say a sloth, is infected with two different strains of
Speaker 2: this virus at the same time, it can lead to
Speaker 2: a mixing up of different chunks of their genome and
Speaker 2: result in a completely new version of this virus, often
Speaker 2: one that is drastically different than either of the so
Speaker 2: called parent viruses. There's actually a few other viruses that
Speaker 2: have different names, Equito's virus, Madre de Dios virus, and
Speaker 2: perdos virus. I might be pronouncing that one wrong, which
Speaker 2: that one doesn't infect humans, but these contain parts of
Speaker 2: the oropushe virus and then another segment from a related
Speaker 2: virus in the same what we call zero group, the
Speaker 2: same group of viruses. So yes, the fact that oropush
Speaker 2: can recombine is a really important aspect of the like
Speaker 2: virology of this virus, and we think it was probably
Speaker 2: involved in the most recent outbreak that we saw twenty
Speaker 2: twenty four twenty twenty five, and we'll talk a little
Speaker 2: bit more about that later in this.
Speaker 1: Episode, changing virulence patterns and all of those things.
Speaker 2: Yeah, and speaking of transmission, so this is a virus
Speaker 2: that is transmitted via vectors, right via these biting midges.
Speaker 2: There has not been shown so far any direct human
Speaker 2: to human transmission, so even if you're sick and miserable,
Speaker 2: you're not transmitting it to other people. However, similar to
Speaker 2: zica virus, there is now evidence that our push can
Speaker 2: be transmitted across the placenta, so if someone is infected
Speaker 2: while they're pregnant, it can infect the fetus, and it's
Speaker 2: been thought to be associated with a number of stillbirths,
Speaker 2: fetal losses, so miscarriages, and things like microcephaly, which is
Speaker 2: when the brain does not fully develop, similar to how
Speaker 2: we saw with zicavirus. Unlike with zecavirus, we don't know
Speaker 2: enough about the virology yet to understand what's going on
Speaker 2: or how common or any of that. But epidemiologically, this
Speaker 2: pattern seems to have come out of this most recent
Speaker 2: outbreak that we've seen, and so we do think that
Speaker 2: it's crossing the placenta and can cause damage to the fetus,
Speaker 2: which is pretty serious.
Speaker 1: But no sexually transmitted or great question. Great question.
Speaker 2: At least one paper that I saw said that they
Speaker 2: thought that they had detected it in semen. Does that
Speaker 2: mean that it's able to be transmitted?
Speaker 1: Right? We don't know. It's a huge open question, right, Okay, yep.
Speaker 1: Question about the habits of these biting midges when you
Speaker 1: know how like mosquitoes love down and dusk doesn't mean
Speaker 1: that they don't bite you in other times of day,
Speaker 1: but like where do they bite you? When do they
Speaker 1: bite you?
Speaker 3: Yeah?
Speaker 1: Do I'm assuming because they are their larval stage develops
Speaker 1: in water, that there's like a seasonal or climate component
Speaker 1: to this what's going on?
Speaker 2: You're very right, So there is definitely a seasonal and
Speaker 2: climate component. So we see that the highest burden of
Speaker 2: these of our push virus tends to be during rainy season,
Speaker 2: and that's going to be when you have more water
Speaker 2: available for larva to you know, mature and for the
Speaker 2: females to lay their eggs and things like that. So
Speaker 2: that's definitely the case. In terms of when exactly they bite,
Speaker 2: they can potentially be kind of throughout the day. They
Speaker 2: do tend to be done in dusk, similar to a
Speaker 2: lot of some mosquito species. Not all mosquitoes are like that,
Speaker 2: but like I said, because they can't bite through clothing,
Speaker 2: they're going to tend to go towards areas that are
Speaker 2: more available. So a lot of times they're biting on legs,
Speaker 2: they're biting on arms, they're betting on things that they
Speaker 2: can actually access, and they're really voracious.
Speaker 1: Their bites hurt.
Speaker 2: And then beyond that, there's probably more that either I
Speaker 2: don't know or that we don't know yet about about
Speaker 2: these vectors.
Speaker 1: And maybe you're getting there in the current section. But
Speaker 1: distribution geographic distribution of midge.
Speaker 2: Yeah, So this species of midge is found throughout Central
Speaker 2: and South America and throughout the southern part of North
Speaker 2: America all the way up into like the eastern seaboard.
Speaker 2: You can even find them sometimes in Michigan and Wisconsin
Speaker 2: and things like that, and then all throughout the south
Speaker 2: southern United States. Which is an important part of the
Speaker 2: distribution of this virus so far is that this virus
Speaker 2: has not been found everywhere, but the vector does exist
Speaker 2: far beyond the range that we have seen the virus
Speaker 2: so far.
Speaker 1: Right, which just means potential for spread. Potential for spread, Yeah, exactly, yeah,
Speaker 1: which is also I mean, I know that we'll get there,
Speaker 1: but like the fact that this virus can infect so
Speaker 1: many vertebrates, so many, it seems like, and we don't know,
Speaker 1: we don't know.
Speaker 2: We don't know the extent we from what we have
Speaker 2: found so far, we think sloths, capuchins, howlers, and some birds,
Speaker 2: but like birds is a huge category alone right now,
Speaker 2: it's just fun.
Speaker 1: It's Central and South America, I know, some of the
Speaker 1: most biodiverse areas on this planet, right exactly.
Speaker 2: So yeah, so we don't we don't know, you know,
Speaker 2: And who is playing the biggest role, who is involved
Speaker 2: in the spillover events and why, Like we don't know any.
Speaker 1: Of those things. We don't know. We don't know.
Speaker 2: And as is the case for so many tropical especially
Speaker 2: viral and other infectious diseases, diagnosis remains a really big
Speaker 2: challenge and that severely limits our understanding of the true
Speaker 2: epidemiology and spread of this because you can't diagnose it
Speaker 2: without adequate identification, especially because the symptoms are so nonspecific
Speaker 2: and they overlap so much with other diseases that are
Speaker 2: in the same geographic areas, So you have to have
Speaker 2: access to either serology or like PCR rtPCR, which isn't
Speaker 2: available everywhere, especially in the range of where this virus
Speaker 2: is found. And as with so many other viral illnesses,
Speaker 2: we have no specific treatment for it. We have no
Speaker 2: vaccine and spoiler alert, no vaccines on the horizon that
Speaker 2: I have seen, Like as of twenty twenty two, there
Speaker 2: was like one paper about vaccine development for oro poosh virus.
Speaker 2: So this is pretty neglected viral illness. Yeah, even though
Speaker 2: it's not technically considered a neglected tropical disease yet, which
Speaker 2: is wild.
Speaker 1: I mean, I think it is. It's really interesting to
Speaker 1: read back through some of these outbreaks and epidemics and
Speaker 1: it's like so much, so much a shot I don't
Speaker 1: want to say shot in the dark, but like the
Speaker 1: these estimates are based on the information that was available,
Speaker 1: which is can be very often limited based on what
Speaker 1: you said, how you have to have testing, you have
Speaker 1: to have and because the virus itself is so tends
Speaker 1: to cause these self limited infections. Someone's better in a
Speaker 1: few days. They may never you know, like right, they
Speaker 1: may never know that they had or a push virus exactly. Yeah.
Speaker 2: Yeah, And so our estimates are very very limited, but
Speaker 2: that aaron is or a push.
Speaker 1: Can you tell me where it came from?
Speaker 4: I can, I can okay.
Speaker 1: On September twenty sixth, nineteen fifty five, a twenty four
Speaker 1: year old man entered the fever clinic that was run
Speaker 1: by the Trinidad Regional Virus Laboratory in Sangre Gerondi, Trinidad.
Speaker 1: I love that there's a fever clinic. Oh, there'll just
Speaker 1: I'll tell you more about it. He hadn't been feeling
Speaker 1: ill for very long, just like one day, and his
Speaker 1: symptoms weren't too extreme. He had just had a back
Speaker 1: ache and a little cough, no sore throat, with the
Speaker 1: exception of his fever, which was one hundred and four
Speaker 1: degrees fahrenheit. Oh, pretty high, pretty high. I didn't write
Speaker 1: that down in celsius, but it's high high thirty over
Speaker 1: forty maybe over forty maybe forty. Yeah. He was referred
Speaker 1: to this clinic, which was kind of standard practice at
Speaker 1: the time, but his symptoms were so vague that it
Speaker 1: was like, well, we don't really know what this could be.
Speaker 1: Let's run some standard tests, which included, you know, looking
Speaker 1: at blood smears under the microscope. There was one smear
Speaker 1: that looked like maybe there was one single malaria parasite,
Speaker 1: but it wasn't conclusive, and then people who looked at
Speaker 1: it later were like, there's nothing here. So it was
Speaker 1: kind of like, well, this guy got better really quickly.
Speaker 1: His illness lasted three days total. In normal circumstances, like
Speaker 1: in many of the time, we would think that like
Speaker 1: that person would fly under the radar and you're done
Speaker 1: with that. That's not what happened. And in retrospect, it's
Speaker 1: kind of amazing that he made it to the clinic
Speaker 1: in the first place while that illness was still ongoing,
Speaker 1: which meant that the doctors could the researchers there could
Speaker 1: take blood samples while he was acutely ill, so then
Speaker 1: they could take that blood and run more tests on it.
Speaker 1: So they took serum from that blood sample gave it
Speaker 1: to mice who died, which suggested that a path gen
Speaker 1: virus was involved. What virus was it? Like, this is
Speaker 1: not this is this is concerning right, that's a great question.
Speaker 1: It didn't seem to be one of the usual or
Speaker 1: even one of the unusual suspects, and so it was
Speaker 1: given a new name or a poosh virus. Yeah, why
Speaker 1: or a poosh. Well, the man who had visited the
Speaker 1: clinic that kicked off this pathoge and hunt, he lived
Speaker 1: nearby in a small community called Vega Day or a Push,
Speaker 1: So that's it's a place name. Yeah, where you're from.
Speaker 1: This is yeah, it was before that became against the
Speaker 1: you know, when it was right while naming diseases after
Speaker 1: places was still a conventional thing to do, but subsequent
Speaker 1: tests with the virus revealed that it could cause disease
Speaker 1: in a range of animals like mice, guinea pigs, and
Speaker 1: chicken embryos, so it definitely wasn't nothing to worry about.
Speaker 1: Whether or not those animals could play a strong role
Speaker 1: in it's spread is not clear, but just the fact
Speaker 1: that it could cause disease and death in that right
Speaker 1: is you.
Speaker 2: Could have symptoms. And also they were just like culturing
Speaker 2: this virus from this dude's serum this whole time.
Speaker 1: Yeah, wow, I know, I know, he.
Speaker 2: Just went to the best possible climate. Come yeah, I
Speaker 2: mean he got better on his own, so I guess
Speaker 2: think he got much for him.
Speaker 1: But right right, they were running all these test finding
Speaker 1: that it was indeed some sort of you know, previously
Speaker 1: undescribed potentially pathogenic or seemingly pathogenic virus. Where did it
Speaker 1: come from? And this was the question that the Trinidad
Speaker 1: Regional Virus Laboratory was very motivated and equipped to answer.
Speaker 1: The first clue came from the patient himself. Although he
Speaker 1: resided in the village like most of the time vegadevo
Speaker 1: or Pousche, for two weeks before his illness, he had
Speaker 1: actually been working and sleeping in a forest a few
Speaker 1: miles away where he worked as a charcoal burner. Okay,
Speaker 1: so if you didn't know, I certainly did not. A
Speaker 1: charcoal burner is someone who makes charcoal by burning a
Speaker 1: bunch of woods, you know, deforested area chopped out a
Speaker 1: bunch of trees. You burn those trees and you have
Speaker 1: to stand by your your charcoal pit for weeks, often
Speaker 1: on end, while the charcoal is being made. It's a long,
Speaker 1: lonely job. There's even like a poem by the creator
Speaker 1: I think of we need the pooh about it, like
Speaker 1: how sad it is. And because you have to stay
Speaker 1: by your charcoal pit in the woods around where no
Speaker 1: one else is there. It's not like this is a
Speaker 1: group activity. Oh Okay, and so learning that this guy
Speaker 1: was a charcoal burner, it immediately set off red flags
Speaker 1: for the researchers because they were like, Okay, you are
Speaker 1: spending a lot of time in the forest. This suggests
Speaker 1: that it's probably vector borne. There's probably a mosquito or
Speaker 1: something else out there. This is a spillover event. I
Speaker 1: love that they that that ough. I love this story,
Speaker 1: Aaron keeping, and so they went out there. In the
Speaker 1: nineteen sixty one paper that first describes as virus, quote,
Speaker 1: when it became evident that an agent pathogenic for mice
Speaker 1: had been isolated from a forest, steps were taken to
Speaker 1: attempt recovery a virus from blood sucking diurnal insects prevalent
Speaker 1: about the patient's home and charcoal pit in the forest. Reasonable.
Speaker 1: Next story, very very and mostly as far as I
Speaker 1: could tell, it was mosquito species that were collected, and
Speaker 1: none of them seemed to be the clear culprit, although
Speaker 1: it did suggest that there was, like I think in
Speaker 1: a later collection. In a later paper, they found one
Speaker 1: instance of the virus in a mosquito. So they were like, okay,
Speaker 1: well that doesn't rule it out, but it's clearly not
Speaker 1: mosquito's entirely. They did also do antibody testing in some
Speaker 1: animals like primates, and they found that yes, some primates
Speaker 1: seem to have been exposed to this virus previously, and
Speaker 1: so this suggested that oropush virus was not uncommon in wildlife. Also,
Speaker 1: they like developed an antibody test for it already. I know,
Speaker 1: I'm amazed. I can't wait to tell you were okay
Speaker 1: this was I will say, like it's you're amazed, right,
Speaker 1: Like it's really cool to look at this, beautiful Like okay, logical,
Speaker 1: next steps. You have the resources to look at this,
Speaker 1: you understand what you're looking for all this stuff, right,
Speaker 1: This was not front page news even in the world
Speaker 1: of viruses because it was first of all, viruses are
Speaker 1: very diverse. There are so many undiscovered viruses out there.
Speaker 1: And this was one person this who had recovered quickly.
Speaker 1: This was yeah, this was a handful of howler and
Speaker 1: capuchin monkeys that showed past infection. Maybe an infected mosquito
Speaker 1: or two. I mean, this was one of an untold
Speaker 1: number of viruses circulating in wildlife that remained to be name.
Speaker 1: It was like, who cares, Okay, so you found a
Speaker 1: new virus right. It was like, thank you for recording
Speaker 1: that information. Right, we'll add it to our list of
Speaker 1: thousands of viruses, right, just like this. Yeah. And also
Speaker 1: maybe it was a fluke. Maybe this was a one
Speaker 1: time event that happened. And the next five years of
Speaker 1: silence that surrounded this vires seemed to suggest that that
Speaker 1: was actually the case, until it popped up again in
Speaker 1: nineteen sixty, this time in an entirely different country, over
Speaker 1: one thousand miles away. Ooh, not good, not good, well intriguing, yeah,
Speaker 1: and not good. A three toad sloth in northern Brazil
Speaker 1: was found to be infected with the virus in a
Speaker 1: way kind of foreshadowing the sizeable epidemic that would occur
Speaker 1: in the region in the following year. So in nineteen
Speaker 1: sixty one, and estimated eleven thousand people were infected with
Speaker 1: ore A push virus in the same region. Oh wow.
Speaker 1: And so, as it turned out, no, yeah, that not
Speaker 1: only was that first nineteen fifty five case not a
Speaker 1: one off, this epidemic would also be just the first
Speaker 1: in a series that occurred over the next decades, as
Speaker 1: the virus spread to much of Central and South America
Speaker 1: and especially throughout Brazil.
Speaker 2: So, but they were able to identify it as or
Speaker 2: a pushe virus because of the work of the people
Speaker 2: who identified it.
Speaker 1: Yeah, nineteen fifty five. That's incredible. There's yeah, because of
Speaker 1: this work, because of this network of information, this virus
Speaker 1: was able to be name, described, identified, and linked to
Speaker 1: an outbreak. That's it's pretty it's pretty impressive. It's very impressive. Yeah.
Speaker 1: And over the next decades, I'm kind of like squeezing
Speaker 1: a lot in here, the numbers kept climbing. So between
Speaker 1: nineteen seventy eight and nineteen eighty one and estimated two
Speaker 1: hundred and twenty thousand cases, thirty outbreaks along the Amazon
Speaker 1: River between nineteen sixty one and nineteen ninety six, with
Speaker 1: an estimated half a million cases, and most of these
Speaker 1: are in Brazil. And it wasn't just the number of
Speaker 1: cases that kept growing though, it was also the virus's
Speaker 1: geographic distribution. First there was that case, the individual case
Speaker 1: as far as we knew, in Trinidad. Then there was
Speaker 1: the outbreak in northern Brazil, then all along the Amazon River,
Speaker 1: then in these non endemic regions of Brazil than in Panama, Peru, Ecuador, Bolivia, Venezuela, Haiti, Colombia,
Speaker 1: French Guyana. You just like, yeah, Guatemala, Cuba, on and on, just.
Speaker 2: To all of these, all of these places, by the way,
Speaker 2: that don't all touch and are not all that close
Speaker 2: geographically necessarily.
Speaker 1: Some of these cases are you know, whether or not
Speaker 1: this indicates local spread. I'll let you answer that later on.
Speaker 1: But the increasing number of countries that are reporting this
Speaker 1: virus at all shows two things. It shows that the
Speaker 1: potential for increased geographic spread, and it also shows an
Speaker 1: increased awareness becauset better detection and awareness might be driving
Speaker 1: some of this because for decades or a pooshe virus
Speaker 1: cases were probably wrongly ascribed to dengey or like outbreaks.
Speaker 1: So like how many of the past and gay outbreaks
Speaker 1: were actually or pooh, could it r mix this kind
Speaker 1: of stuff or checking don yet like they're all so
Speaker 1: they're all so kind of similar. Yeah, but there's there
Speaker 1: is no doubt that this disease is on the move
Speaker 1: and it might actually be evolving to become more virulent,
Speaker 1: you know some recent cases, or it has the potential
Speaker 1: to become more virulent. Given what you told us, Aaron
Speaker 1: about the virus's characteristics. You know, it's high mutation or
Speaker 1: recombination rate, multiple insect vector hosts, and multiple vertebrate reservoirs.
Speaker 1: This is not entirely surprising that we're seeing this kind
Speaker 1: of spread, but it is concerning and it begs a
Speaker 1: few questions. Where did this thing come from? Again? And
Speaker 1: how is it spreading so quickly? H And why was
Speaker 1: anyone looking for viruses and sloths in the first place? Yeah,
Speaker 1: that's what I want to know.
Speaker 2: Who tasted that slothyting that slot?
Speaker 1: Okay, we're going to answer the first two questions. First,
Speaker 1: I could do this pretty quickly, or a push virus
Speaker 1: probably originated in Brazil anywhere from Prepare yourself for a
Speaker 1: wide range. Wide range here eighty to three hundred and
Speaker 1: sixty years ago. Smaller range than we have for a
Speaker 1: lot of other things.
Speaker 2: Wait wait, wait, eighty to three hundred and sixty Yeah.
Speaker 1: Wow, so it's super new, super new three it's the
Speaker 1: oldest they think it is is in the hundreds of years. Okay,
Speaker 1: but here's here's the thing that I I kind of
Speaker 1: have questions about because we talked about how it has
Speaker 1: these different like the segment to genome with a lot
Speaker 1: of reassortment, and so our existing data is like the
Speaker 1: diversity of these viruses is maybe not reflective of the
Speaker 1: overall history. I'm not sure, but I was thinking about
Speaker 1: how flu we have complete extinct viral lineages right right right,
Speaker 1: So whether.
Speaker 2: That's called those different viruses or would we Yeah, it
Speaker 2: is because the zero group that or a push belongs
Speaker 2: to is called the Simbu zero group. And I had
Speaker 2: a really hard time sorting through, like are these different genotypes?
Speaker 1: Are these different viruses?
Speaker 2: Are these different and there are a number that they
Speaker 2: classify as different viruses even though they are quite similar.
Speaker 1: So yeah, it is.
Speaker 2: It is a confusing phylogeny of that whole group, including
Speaker 2: or a poosh virus, So that I guess makes sense
Speaker 2: in that way. So like the Simbu zero group is
Speaker 2: probably much older, but or a poosh itself, who knows.
Speaker 4: I don't know.
Speaker 1: I don't know. I mean I do think that it's
Speaker 1: like there are viruses that emerge or evolve, and when
Speaker 1: when does a new virus become a new virus? I
Speaker 1: think is a that's a question.
Speaker 3: For a virologist philosophical question too, or a philosopher, sure,
Speaker 3: but I think that whenever it originated, it has seemed
Speaker 3: to expand relatively recently, like it's only in the last
Speaker 3: few decades that it's expanded across the most of South
Speaker 3: America and Central America.
Speaker 1: Why it has done so is because of humans. Bottom line,
Speaker 1: deforestation and widespread movement of humans created the perfect conditions
Speaker 1: for aur poosh virus spillover and spread as forests were
Speaker 1: cut down. That led to more opportunities for infected mosquitoes
Speaker 1: to bite the humans living on the forest edges. So like,
Speaker 1: think about the construction of that highway highway and then
Speaker 1: increased movement for humans, both short scale like from deforested
Speaker 1: region to city and then long scale from one city
Speaker 1: to another region or another country drove the spread of
Speaker 1: this virus. So consider, if you will, the sequence of events.
Speaker 1: Someone is working on the construction of a road through
Speaker 1: a newly deforestd region of the Amazon, for instance, like
Speaker 1: the road that we discussed in our first hand One day,
Speaker 1: they're bitten by a midge that's infected with or push virus.
Speaker 1: A few days later, they take their day off to
Speaker 1: drive back to their nearby city to visit with some
Speaker 1: friends and family. There, a midge bites them, picks up
Speaker 1: the virus. That midge then bites someone else, infecting them.
Speaker 1: Another midge bites that person, and suddenly you've got an
Speaker 1: epidemic on your hands. This is how one spillover event
Speaker 1: can lead to sizeable outbreaks. And the story doesn't end there.
Speaker 1: So now, let's say somebody else was in town during
Speaker 1: this outbreak, and they also happened to be working on
Speaker 1: road construction in a newly deforested area, but in another
Speaker 1: part of the country or another country entirely where or
Speaker 1: push virus is not present. They get infected during this
Speaker 1: city outbreak, head back to their work site, where another
Speaker 1: midge bites them, becomes infected, then bites a sloth or
Speaker 1: a howler monkey, Another midge or a mosquito picks up
Speaker 1: the virus, and then suddenly or a pushes endemic in
Speaker 1: this new forested region. This is spillback, spill it over,
Speaker 1: spill back into two wildlife. Spill bat doesn't get talked
Speaker 1: about enough.
Speaker 2: I feel, no, it doesn't, It really doesn't. But yeah,
Speaker 2: it's an important part.
Speaker 1: It is a really important part, and I wanted to
Speaker 1: mention before I forget that I'm wearing my spillover. I'm
Speaker 1: gonna call it my spillover sweater today. Yep, it's got
Speaker 1: If you're watching on YouTube, you can see this. It's
Speaker 1: got a woodpecker, it's very cute, and some little squirrels, squirrels,
Speaker 1: it's very cute, so cute. So it's from now on,
Speaker 1: anytime we do another Oh, I've got it. I've got it,
Speaker 1: cuts down on decision making. It's wonderful, fantastic spillover in
Speaker 1: spillback for aur a poosh virus, they're not just like
Speaker 1: likely to happen, but there they have happened, and they
Speaker 1: are likely to result in sustained transmission or turning an
Speaker 1: uninfected area into an endemic one. And this is for
Speaker 1: for all the things that we've already talked about, right,
Speaker 1: the wide host range, the recombination multiple potential different species
Speaker 1: of vectors. We don't really know. I mean, this virus
Speaker 1: is like it has never heard of a dead end host.
Speaker 1: It's just like, so what it seems like, what's the
Speaker 1: It's all about those borders between humans and wildlife becoming
Speaker 1: more porous due to human activities like deforestation. In fact,
Speaker 1: deforestation in the Amazon rainforest in Brazil from the nineteen
Speaker 1: fifties to the nineteen eighties coincided with two hundred arboviruses
Speaker 1: being discovered in the region. So oropush is not the exception,
Speaker 1: but it is rather the rule. In fact, roughly seventy
Speaker 1: five percent of all emerging infectious diseases have an animal origin,
Speaker 1: and seventy percent of those come from wildlife. Yeah, wildlife.
Speaker 1: I've got some good stats too, got so good.
Speaker 3: That's yeah, wildlife like the sloth, who is the subject
Speaker 3: of our third question.
Speaker 1: Why were people looking at sloth viruses?
Speaker 3: Anyway?
Speaker 1: I love that someone funded this, so give it to me. Okay, Okay, So,
Speaker 1: given what I just said about the high proportion of
Speaker 1: human pathogens that come from animals, maybe the answer is
Speaker 1: self evident, like why someone was looking at a sloth well,
Speaker 1: because wildlife can carry viruses. But I want to dig
Speaker 1: a bit deeper, exploring not only why researchers were examining
Speaker 1: wildlife for new pathogens in the mid twentieth century, but
Speaker 1: also the infrastructure that allowed them to do so. Both
Speaker 1: the first described case of our poush virus and this
Speaker 1: isolation from a three toad sloth took place at two
Speaker 1: viral research institutes, one in Trinidad and one in northern Brazil.
Speaker 1: Both of these institutes, the Trinidad Regional Virus Laboratory and
Speaker 1: the Belem Virus Laboratory, were established and funded at least
Speaker 1: in part by the Rockefeller Foundation in the mid twentieth century. Okay, interesting,
Speaker 1: we've encountered the Rockefeller Foundation before on this podcast, maybe
Speaker 1: most notably during our hookworm episode. The organization, which was
Speaker 1: started by one of the wealthiest people in history, it
Speaker 1: played a pivotal role in eliminating hookworm in the early
Speaker 1: nineteen hundreds in the southern US. Or at least that
Speaker 1: If that part is controversial or for debate, sure that's fine.
Speaker 1: What it did is it at least elucidated some of
Speaker 1: the factors that sustained its transmission, and over the following decades,
Speaker 1: the Foundation broadened its goals beyond the US. Its mandate,
Speaker 1: as set out in nineteen oh nine, was quote to
Speaker 1: promote the well being and to advance the civilization of
Speaker 1: the peoples of the United States and its territories and possessions,
Speaker 1: and of foreign lands, in the acquisition and dissemination of knowledge,
Speaker 1: in the prevention and relief of suffering, and in the
Speaker 1: promotion of any and all of the elements of human
Speaker 1: progress end quote. Okay, it's a notable goal. Yeah. I
Speaker 1: wish more billionaires would take up philanthropy instead of the
Speaker 1: other alternatives. Yeah, yeah, But I think it would be
Speaker 1: incomplete to view this foundation or the field of tropical
Speaker 1: medicine as a whole, as solely philanthropic, whether in intent
Speaker 1: or impact. Philanthropy was part of it, but it was
Speaker 1: not all. Why were people trying to better understand how
Speaker 1: yellow fever was transmitted or how to prevent leshmaniasis in
Speaker 1: part the Panama Canal exactly so that imperialist powers like
Speaker 1: the US and England could install local governments without people
Speaker 1: dying of infection. Infectious disease in these regions became the
Speaker 1: first hurdle to overcome in you know, settlement, whatever that meant, like,
Speaker 1: you must first conquer infectious diseases before you can conquer
Speaker 1: this nation. Scientific and medical knowledge may have benefited the
Speaker 1: populations under imperialism, it did not always, and if it did,
Speaker 1: it often came. Those benefits came much later on, and
Speaker 1: it came with tremendous costs. That knowledge was not freely shared,
Speaker 1: and in some cases it wasn't shared at all. The
Speaker 1: colonizers were often the only ones to benefit from that
Speaker 1: knowledge or have the capacity to implement it. Oh, screens
Speaker 1: prevent mosquitoes, which could then prevent yellow fever. Put those
Speaker 1: screens in our houses, our houses. Yeah, clean water screens,
Speaker 1: bugsprit medications, stuff like that. That was not like, oh,
Speaker 1: and then now here it is everyone. He was not
Speaker 1: in the age of imperialism from the late eighteen hundreds,
Speaker 1: so the early nineteen hundreds, scientific progress was not democratized,
Speaker 1: and the concurrent rise of germ theory enabled the use
Speaker 1: of tropical medicine as a tool of imperialism. The Rockefeller
Speaker 1: Foundation which emerged as this period was winding down. As
Speaker 1: the age of imperialism was winding down, it seemed from
Speaker 1: my reading, less focused on conquer and more on capitalism,
Speaker 1: which is unsurprising given Rockefeller's prowess as a businessman. He
Speaker 1: saw progress, particularly economic progress, as viewed from a capitalistic
Speaker 1: Western perspective. He saw this progress as being hindered by
Speaker 1: poor health. It wasn't just that life was being cut short,
Speaker 1: it was also labor and productivity. Similar to how today
Speaker 1: we use the metric disability adjusted life years to measure
Speaker 1: the impact of a disease, right, Rockefellers saw that improving
Speaker 1: the overall health of a region through public health interventions
Speaker 1: would ultimately lead to greater economic prosperity, which was great
Speaker 1: if the region was under the control of the US,
Speaker 1: but if it wasn't, then that also meant more money
Speaker 1: to be pumped into the global capitalism machine, which predominantly
Speaker 1: benefited Western imperialist powers. So it's kind of a yes
Speaker 1: and situation. Yeah, So the virus labs and other Rockefeller
Speaker 1: initiatives absolutely reduce the overall disease burden in certain areas,
Speaker 1: and they advanced scientific and medical knowledge and the US
Speaker 1: and probably Rockefeller and his descendants enjoyed some of the
Speaker 1: economic benefits from those efforts. Maybe that feels like a
Speaker 1: touch cynical or something.
Speaker 2: I mean, but we've always said like how much money
Speaker 2: you save with public health and how investment in public
Speaker 2: health is. Like it's just like it's a clear example
Speaker 2: of someone having enough money to do that, which is
Speaker 2: really interesting, fits.
Speaker 1: Simple, right, And it's like it's kind of one of
Speaker 1: these things where it's like we're money or public health
Speaker 1: is money saving, it's not revenue generating, right, And so
Speaker 1: investment in public health ultimately is like the smartest thing
Speaker 1: that you can do as an economic power. Are billionaires
Speaker 1: listening right, right? And so it's like, Okay, if we
Speaker 1: can't convince you to do this out of the good
Speaker 1: you know, good for mankind, just to have a leave
Speaker 1: a legacy that means something more than just consumer and
Speaker 1: profiting off of whatever, right, all of that, then let
Speaker 1: us convince you because it makes more financial sense to
Speaker 1: do so it will eventually save us a lot of money. Yeah, yeah,
Speaker 1: but it still feels like it still feels a little
Speaker 1: bit cynical. And so I also, I don't know. I
Speaker 1: wanted to also add that I think that the researchers
Speaker 1: and probably the organizers the administrators of this foundation who
Speaker 1: were involved and wanted to take part in these efforts,
Speaker 1: I think that they probably or possibly had good intentions,
Speaker 1: like the purest of intentions. Right. Maybe they went into
Speaker 1: this field to reduce human suffering, to devise new vaccines,
Speaker 1: to identify pathogens, or simply just add to this body
Speaker 1: of knowledge to help make the world a better place.
Speaker 2: Well, and like a bunch of nerds getting to actually
Speaker 2: do this important science, Like.
Speaker 1: Are you kidding me? It's the dream, and it's not
Speaker 1: like local populations where these labs were established were just
Speaker 1: like passive players. Many citizens and regional governments became directly
Speaker 1: involved in primary research as well as the application of
Speaker 1: that knowledge and in funding. It was often like meeting
Speaker 1: the funding need. Yeah. From nineteen fifty to nineteen seventy,
Speaker 1: the Rockefeller Foundation provided the arbovirus program with thirty million
Speaker 1: dollars in funding, which is worth about two hundred and
Speaker 1: thirty million dollars in today's and many local governments directly
Speaker 1: matched that funding. Wow, it's it's kind of staggering when
Speaker 1: you think about what a force that must have been
Speaker 1: and how investment in basic research really has pays off.
Speaker 1: It pays off.
Speaker 2: I just still can't get over the fact that they
Speaker 2: found this virus from one dude, and then within a
Speaker 2: couple of years we're able to identify outbreaks that easily.
Speaker 2: I mean, how many times have you told a story
Speaker 2: on this podcast, Aaron where it's like, yeah, someone found
Speaker 2: this virus and named it, but then decades later, someone
Speaker 2: else found this virus and they thought they were the
Speaker 2: first person ever to identify it.
Speaker 1: Like that's usually how these stories go. It's usually how
Speaker 1: it goes. I think part of it has to do
Speaker 1: with when this like the historical context of when this
Speaker 1: was happening, and so in a lot of those cases
Speaker 1: there was not the technology or the scientific know how
Speaker 1: to be like, this is a virus at.
Speaker 2: All, right, or to be able to share that information.
Speaker 2: We'll share the information, yeah yeah.
Speaker 1: So I think this was sort of a confluence of
Speaker 1: we have the equipment to do this, we have the
Speaker 1: minds to do this, we have the funding, and we
Speaker 1: have this this network of information that can be spread
Speaker 1: and the incentive to identify this like, hey, here's this money,
Speaker 1: find out what you can about.
Speaker 2: About arboviruses, and so that's what they were doing with
Speaker 2: this sloth. But they were like, we've got money to
Speaker 2: find viruses, and so we're going to test a bunch
Speaker 2: of animals anywhere. Oh yeah yeah, but that was my
Speaker 2: dream job for TI.
Speaker 1: So these Rockefeller Foundation virus laboratories were established initially to
Speaker 1: keep better track of the yellow fever virus, which had
Speaker 1: caused deadly outbreaks in Central and South America in the
Speaker 1: early decades of the twentieth century and had hindered the
Speaker 1: US progress in building the Panama Canal check out our
Speaker 1: yellow fever episode. It also had been in the US
Speaker 1: for a long time. Blah blah blah. Yeah, anyway, Hamilton
Speaker 1: Hamilton Field Laboratories were established not just in Trinidad and Brazil,
Speaker 1: but also Egypt, India, South Africa, Nigeria and Colombia. And
Speaker 1: as researchers uncovered more information about the ecology of yellow fever,
Speaker 1: its mosquito vector, its vertebrate hosts, how climate induced its transmission,
Speaker 1: two things happened, at least. The first was that in
Speaker 1: their ecological studies of yellow fever, they were also finding
Speaker 1: other arthropod born viruses that had never been described. You know,
Speaker 1: test this mosquito, screen, this monkey, sloth, etc. Oh, that's
Speaker 1: something we haven't seen before. Let's dig a little bit deeper.
Speaker 1: The second is that they were leveraging their knowledge about
Speaker 1: yellow fever to make meaningful, sustained progress in its control.
Speaker 1: If you could make such headway against a long feared,
Speaker 1: deadly disease, maybe you could do the same for these
Speaker 1: new viruses that you were finding. Identify the arthropod vectors,
Speaker 1: figure out which vertebrates act as reservoir host, measure affection
Speaker 1: against climatic or seasonal variables and then use all that
Speaker 1: information to disrupt the chain of transmission and prevent disease.
Speaker 1: Even though it wasn't called that at the time, this
Speaker 1: embodies a one health approach where animal, human, and environmental
Speaker 1: health are all taken into consideration. Historically, after the early
Speaker 1: years of germ theory and epidemiology, where animals and the
Speaker 1: environment were more likely to feature in studies alongside human disease,
Speaker 1: these different fields were often siloed so like there was
Speaker 1: pre germ theory, it was like, oh, the weather has turned,
Speaker 1: this might lead to an outbreak of plague, you know
Speaker 1: that kind of thing. Once we found one bacteria, one disease,
Speaker 1: that sort of segmented segmenting, chopping up these diseases into
Speaker 1: discrete entities. That also meant that specialties were also segmented
Speaker 1: and siloed, like a biomedical researcher wasn't necessarily inclined to
Speaker 1: observe a disease under natural conditions. If a lab environment
Speaker 1: and an experimental animal could suffice like you could control
Speaker 1: the ecological noise much better that way, and collaborations between
Speaker 1: physicians and veterinarians dwind as the fields grew more specialized
Speaker 1: who's got the time? Or you would have to learn
Speaker 1: a lot more about like a horse's guts than you
Speaker 1: were prepared to. One area, though, that resisted such rigid
Speaker 1: boundaries among disciplines was that of medical entomology and tropical medicine.
Speaker 2: Oh love that, And these.
Speaker 1: Were the two areas in which the Rockefeller Foundation was
Speaker 1: heavily involved. How could you predict the movement of a
Speaker 1: mosquito born virus without considering the mosquito itself, right, you.
Speaker 2: Cannot, and all the other things they're feeding on, and
Speaker 2: their environment and where they're living, and yes, how hot
Speaker 2: it is and how long it takes for their larmy
Speaker 2: to develop, and how long they live.
Speaker 1: And it's the environment, it's the wildlife, it's the domestic animals,
Speaker 1: it's humans, it's all of these things.
Speaker 4: Yeah.
Speaker 1: So the Rockefeller Virus Labs, staffed as they were by
Speaker 1: researchers interested in cycles of infectious disease and natural environments,
Speaker 1: they were well positioned to ask and answer these questions
Speaker 1: of what about the mosquito, what about the wildlife? What
Speaker 1: about the environment, what about the climate and the weather,
Speaker 1: And so hopefully that answers the question of why people
Speaker 1: were looking at sloth viruses in the first place. This
Speaker 1: one health approach is not just one lens through which
Speaker 1: to view a disease like or a push fever. It's
Speaker 1: the only lens that we should be looking at this right. Fortunately,
Speaker 1: that is the framework that many researchers are using today
Speaker 1: to better understand what this virus might have in store
Speaker 1: for the future. Speaking of the future, Erin, could you
Speaker 1: tell me where we stand with or a push virus today?
Speaker 2: I would love to, Erin. I have some stats to
Speaker 2: start you off with GAT. It's very similar to some
Speaker 2: of the ones that you hit us with ARIN. According
Speaker 2: to a paper from twenty twenty four in the Lancet,
Speaker 2: Infectious Diseases, vector born disease specifically, vector born diseases account
Speaker 2: for nearly twenty nine percent of all emerging infectious diseases.
Speaker 2: Of all emerging infects disease are vector born and arboviruses specifically,
Speaker 2: so viral vector diseases are forty percent of all pathogenic
Speaker 2: viruses found in humans from the late eighteen hundreds through
Speaker 2: twenty ten.
Speaker 1: Yeah, yeah, I don't know. I feel like I'm doing
Speaker 1: a research for my dissertation.
Speaker 2: I know, and it is it is bringing me back
Speaker 2: in a way that I didn't realize how much I
Speaker 2: missed this. The true burden of arboviral diseases is not
Speaker 2: known period. However, we do know that over the last
Speaker 2: several decades the global burden has been increasing, not decreasing. Yeah,
Speaker 2: and or a push virus. I am just so shocked
Speaker 2: that I did not know about this. Like when we
Speaker 2: were in grad school, I had not heard of or
Speaker 2: a push virus, which is so weird because we were
Speaker 2: so deep in this world.
Speaker 1: Well, I think that also just shows silos again, Like again,
Speaker 1: it wasn't directly applicable to our readings and our research exactly.
Speaker 2: It is and has been considered one of the most
Speaker 2: prevalent arboviruses, where it's documented second only to dengay virus.
Speaker 1: It's very prevalent.
Speaker 2: It's very very prevalent. We think that there has been
Speaker 2: at least half a million cases, at least five hundred
Speaker 2: thousand cases, and that is almost certainly an underestimate because
Speaker 2: of so much of what you talked about, Aaron, that like,
Speaker 2: we didn't know until we were able to identify this,
Speaker 2: we didn't know that it existed. How many times between
Speaker 2: then and before then and now has this been misidentified
Speaker 2: as malaria, as dengae, as zika, as chicken gunya, as
Speaker 2: so many other viral illnesses. But even as of twenty seventeen,
Speaker 2: the research at least to that time had suggested that
Speaker 2: it was only found in a few countries which were
Speaker 2: not all geographically that close, because by then twenty seventeen
Speaker 2: paper it was like Panama, Brazil, Peru, Trinidad and Tobago,
Speaker 2: and that's not the entire the entirety of its range.
Speaker 2: And we know now from the most recent outbreaks that
Speaker 2: that is definitely not the entirety of its range. We
Speaker 2: also know from a few more recent outbreaks that the
Speaker 2: attack rate of this virus, so if it gets into
Speaker 2: a community, how many people isn't likely to infect might
Speaker 2: be quite high.
Speaker 1: Seems like it. It seems like it.
Speaker 2: There was an outbreak in twenty twenty in French Guiana
Speaker 2: where about forty three percent at least of a population
Speaker 2: was infected in one outbreak. And there haven't been that
Speaker 2: many sero prevalence studies, but the ones that have been
Speaker 2: done in Colombia and Brazil have found between ten and
Speaker 2: sixteen percent of people in the regions that they've studied
Speaker 2: show evidence of prior infection with oropusch virus.
Speaker 1: Wow, I know, I know.
Speaker 2: But the biggest news with Ora pouch virus, and the
Speaker 2: reason that we started getting email requests for this back
Speaker 2: in twenty twenty four, is that there was a very
Speaker 2: very large multi country outbreak that spanned really it started
Speaker 2: in like the end of twenty twenty three, but especially
Speaker 2: twenty twenty four and twenty twenty five, that spread across
Speaker 2: at least eleven countries, including Bolivia, Brazil, Colombia, Cuba, Ecuador, Guyana, Panama, Peru,
Speaker 2: and with travel associated cases in the US, Canada, Cayman Islands,
Speaker 2: and multiple country trees in Europe. By the end of
Speaker 2: twenty twenty four, there had been over sixteen thousand confirmed
Speaker 2: cases thirty nine thousand suspected cases, and that was not
Speaker 2: the end of the outbreak, because in twenty twenty five,
Speaker 2: an additional thirteen thousand confirmed cases were reported across the
Speaker 2: Americas and another seventeen thousand suspected cases were identified that year.
Speaker 2: And like we talked about in terms of the seasonality
Speaker 2: of this, the vast majority, like we saw several kind
Speaker 2: of outbreak waves. If you look at the graphs. The
Speaker 2: Pan American Health Organization PAHO has a really great you
Speaker 2: can go in and look like month by month and
Speaker 2: look at these graphs of all of these reported cases.
Speaker 2: But the vast majority of these cases were in the
Speaker 2: rainy seasons, which kind of do vary depending on where
Speaker 2: you are. This is a very large range geographically, from
Speaker 2: like the mid Central America and the Caribbean all the
Speaker 2: way into South America. But the outbreak seemed to kind
Speaker 2: of wane by June July of twenty twenty five, and
Speaker 2: since then there have just been sort of sporadic reports.
Speaker 2: It seems like that particular outbreak is over, but was
Speaker 2: incredibly large. It won't be the last, no, absolutely not.
Speaker 2: And in those two years some really big changes also
Speaker 2: seem to have happened with our poosh, not just how
Speaker 2: much more widespread this was, right we saw it in
Speaker 2: countries like Cuba, where we didn't even know that this
Speaker 2: vector species existed. It has now been found in Cuba.
Speaker 2: But when the first cases appeared, people were like, what
Speaker 2: the heck is vectoring it in Cuba? Culicoid's parentsis doesn't
Speaker 2: exist there. Maybe it does, or maybe it was a
Speaker 2: different vector species it's still a little bit unclear, okay.
Speaker 2: But so the geographic spread was astonishing in that it
Speaker 2: was in so many places that we had not previously
Speaker 2: seen it. We also saw the first ever reported deaths
Speaker 2: from our A pooh virus. In twenty twenty four. There
Speaker 2: were two deaths reported, both of them from Brazil, and
Speaker 2: the last majority of these cases were in Brazil across
Speaker 2: both of these years, twenty twenty four and twenty twenty five.
Speaker 2: In twenty twenty four, there were two deaths in Brazil,
Speaker 2: both in two otherwise young women in their twenties, healthy
Speaker 2: with not any known conditions that would put them at
Speaker 2: high risk. And in twenty twenty five there were six
Speaker 2: additional deaths, five in Brazil and one in Panama. And
Speaker 2: that does not count the miscarriages or pregnancy losses and
Speaker 2: still births which we saw that we think were associated
Speaker 2: with Ora push virus, or the congenital malformations that we
Speaker 2: think might be associated so microcephaly and the lack of
Speaker 2: brain development that we have seen in a handful of
Speaker 2: cases as well. Yeah, so huge changes that we saw
Speaker 2: with Ora push virus in the last couple of years
Speaker 2: compared to anything that we had seen previously. Why we
Speaker 2: don't really have great answers. There was Elminho years during
Speaker 2: some of that time, and so we think that, you know,
Speaker 2: the seasonality and the increase in rainfall and things are
Speaker 2: likely associated with that particular outbreak and will be in
Speaker 2: the future.
Speaker 1: Right, just higher numbers of midges for exactly.
Speaker 2: Exactly, And like I said, there are still questions to
Speaker 2: be answered about what was different about this particular viral strain,
Speaker 2: but it does seem like the almost all the cases
Speaker 2: in twenty twenty four to twenty five, these large outbreaks
Speaker 2: were from this kind of novel reassortment where we saw
Speaker 2: a virus that looks quite different than or a push
Speaker 2: viruses that we have seen in the past. And so
Speaker 2: that and how big of a role that played, and
Speaker 2: what about this novel reassortment made it so that this
Speaker 2: outbreak could happen, We still don't know, but it is
Speaker 2: very likely that that played at least part of a role.
Speaker 2: In addition to the vectors and the rainfall and the
Speaker 2: climate and the deforestation and the travel and the globalization
Speaker 2: and all of.
Speaker 1: The past that play. I feel like some things are
Speaker 1: could be If you're thinking about this in terms of
Speaker 1: like a fire, right, some things are the matches and
Speaker 1: some things are the kindling. Yeah, and so it's like,
Speaker 1: what the El Nino year is not the match, but
Speaker 1: it's the kindling, you know, like that that kind of stuff. Yeah,
Speaker 1: I'm curious for the genetic diversity of these viruses in
Speaker 1: that outbreak was all the same.
Speaker 2: As far as I could tell, it does seem to
Speaker 2: be kind of all this big novel reassortment that is
Speaker 2: quite different than any of the other or push viruses
Speaker 2: that we've seen in the past.
Speaker 1: Okay, we have covered a lot of mosquito born and
Speaker 1: arboviruses on this podcast, and there are many, many, many
Speaker 1: more out there that we have not covered. And I
Speaker 1: think sometimes the number just like the sheer diversity of
Speaker 1: sort of like how I was like, well, this is
Speaker 1: not the or A push is not the exception. It's
Speaker 1: the rule. Can paradoxically make you go, oh, well, then
Speaker 1: there are so many like whatever, but or a poosh
Speaker 1: is it is exceptional in many ways, in its its
Speaker 1: ability to spread, in its vector prevalence and distribution, and
Speaker 1: in the increasing frequency, and just sort of also the
Speaker 1: fact that like we're not I worry that the that
Speaker 1: we all have maybe a little bit of headline fatigue
Speaker 1: when it comes to things like this, and it's like
Speaker 1: this inclination to go, oh, it's just an exaggeration or whatever,
Speaker 1: but like, no, I really these things will continue to happen.
Speaker 2: Yep.
Speaker 1: Modern medicine won't prevent us if it's not if it's
Speaker 1: not able to be accessed and not shared equitably, right yeah, yeah, And.
Speaker 2: I mean we still from what I can tell, it's
Speaker 2: not like this has led to a huge boost in
Speaker 2: or A push funding and now we have all these
Speaker 2: vaccines on the horizon. There's not there's none, there's nothing,
Speaker 2: there's I.
Speaker 1: Mean, I certainly don't see that happening with this administration.
Speaker 2: So definitely not Yeah, yeah, no, it's uh. I think
Speaker 2: or a Push is another example of so many that
Speaker 2: we have seen of these will just keep coming. Viruses
Speaker 2: will just keep coming, They will keep spilling over. We
Speaker 2: will keep seeing new ones and.
Speaker 1: The end great stuff.
Speaker 2: Yeah, yeah, We've got lots of people want to read
Speaker 2: more about or a push virus.
Speaker 1: We do, Okay, So I there was a paper from
Speaker 1: twenty twenty four that I really liked. It was by
Speaker 1: Tilston Linnell from twenty twenty four or a push virus
Speaker 1: and emerging Ortho bunya virus. That was great. There were
Speaker 1: a few more there were. Honestly, I have a lot
Speaker 1: of a lot of papers if you're interested in reading
Speaker 1: more about sort of like the Rockefeller and public health
Speaker 1: imperialism perspective. There's a paper from nineteen seventy six by
Speaker 1: Brown titled public Health and Imperialism Early Rockefeller Programs at
Speaker 1: Home and Abroad. And then finally, I just want to
Speaker 1: recommend these papers because it was really interesting to think
Speaker 1: about the on health and where did this where did
Speaker 1: this idea come from? From Anchetta at All From twenty
Speaker 1: twenty one, there are two papers, the Origins and Lineage
Speaker 1: of One Health Part one and Part two. Love it about.
Speaker 1: I also had a number of papers.
Speaker 2: One from twenty seventeen by d Rosa at All from
Speaker 2: the American Journal of Tropical Medicine Hygiene.
Speaker 1: I really liked.
Speaker 2: That was called Aura push virus Clinical Epimological and molecular
Speaker 2: aspects of a neglected Ortho Bunya virus or bunia virus
Speaker 2: I don't know. There was also a review from the
Speaker 2: Lancet Infectious Diseases from twenty twenty four by Wesselman at all.
Speaker 1: The it was.
Speaker 2: Titled Yeah, that was a good one. That was a
Speaker 2: good one, Emergence of Aura push fever in Latin America,
Speaker 2: a narrative review. And then if you want more detail
Speaker 2: on this novel reassortment, there was a Nature Medicine article
Speaker 2: from twenty twenty four by Noveca or Novesa at all
Speaker 2: titled human outbreaks of a novel reassortment or a push
Speaker 2: virus in the Brazilian Amazon Region. And then I also
Speaker 2: want to shout out one that was more focused on
Speaker 2: the vectors themselves by Galley Choate. I'm probably pronouncying that
Speaker 2: wrong and I'm really sorry, And it was from plast
Speaker 2: Neglected Topical Diseases that was called vector Competence for or
Speaker 2: a PUSHFIREUS, A systematic review of pre twenty twenty four experiments.
Speaker 2: It was it was a really good one.
Speaker 1: It's like we don't know anything, I know. I mean,
Speaker 1: I feel like it's like, despite the fact that we've
Speaker 1: kept saying, well, we don't we know, we don't know,
Speaker 1: it's understudied to understuded people. A lot of people have
Speaker 1: done a lot of great work on it, and so
Speaker 1: check out these papers totally. There's a lot. There is
Speaker 1: a lot there. We just we still don't know the comparative.
Speaker 2: To other viral and arboviral illnesses. This has not gotten
Speaker 2: the cell attention or recent reasons funding that it deserves.
Speaker 1: Okay, yeah, okay. Thank you to Bloodmobile for providing the
Speaker 1: music for this episode in all of our episodes.
Speaker 2: Thank you to Tom and Leanna and Pete and everyone
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Speaker 1: Thank you, thank you. Thank you to anyone who enjoys
Speaker 1: this podcast in any way or participates or partakes or whatever.
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Speaker 2: does mean a lot to us.
Speaker 1: It does. It does U. Until next time, wash your
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