#25 – Travel Viruses: Oropouche Virus From the Amazon

00:00:06: What is problematic are infections in pregnant women.

00:00:10: This can lead to fetal death, but it also leads to congenital abnormalities in the newborn and that can include microcephaly.

00:00:46: Hello and welcome to this episode of Virological!

00:00:49: This was recorded on July fourteenths of twenty-twenty six and... third episode in our series of viruses that you can get from mosquitoes during your summer vacation.

00:01:05: The last two weeks we talked about Babadacci fever, in Italy and then also Bogosta disease which is caused by Sintpis virus In Scandinavia.

00:01:17: And maybe you don't want to go to Italy anymore.

00:01:20: You do not wanna go to Scandinavia for your summer vacations?

00:01:23: No, let's go to the tropics.

00:01:25: Why not?

00:01:26: Europe is dangerous too so why not go?

00:01:29: do the tropic right away?

00:01:30: and today we are going talk about Ouro Busch virus.

00:01:35: I think in Spanish it´s called Ourobusche but i think that English pronunciation usually is OuroBUSCH if you don't know how to write this.

00:01:44: its O R O P O U C H E And this virus causes oral push fever.

00:01:55: This is a Punevirus, it's related to other viruses like lacrosse virus which has been transmitted by mosquitoes in the US To humans.

00:02:06: It's related Schmalenberg virus Which is virus that is transmitted to livestock including Europe And it's also more distantly related to the doskana virus that we discussed a while ago, but also more dangerous viruses like green congo hemorrhagic fever virus and rift valley fever virus.

00:02:28: So this virus basically has minus cent single stranded RNA genome.

00:02:36: It has three genomic segments similar to those kind of virus where you had two L or a large segment encodes for the polymerase.

00:02:47: The M-segment, M or middle segment codes for the GNGC glycoprotein and an nonstructural protein that's called NSM.

00:03:01: And then the S-segment codes for nucleoproteins eighty to a hundred twenty nanometers in diameter.

00:03:13: They are typically round but pleomorphic so they're not perfectly round, you can have an egg shape or it could look like the little bit squashed.

00:03:23: and inside we have the RNA that is protected by the RNA genome of these three segments which are protected by nuclear protein And also associated with polymerase Protein.

00:03:39: and then we have a lipid membrane.

00:03:41: And in this lipid, membrane there's we have the spike protein again.

00:03:44: This is here called GNGC and it's called like that because its made as one large protein But then it split into two and We discussed these before.

00:03:55: proteins have to different ends The end terminus and the C-terminus and so Gn Is the part on the N terminals?

00:04:07: We also have several genotypes for aurobush virus and they can mix because we have this genomic segments, which means that it can re-assort.

00:04:15: So if two different versions of aurobusch virus in fact the same animal or human are the same cell then they can exchange these genomics segments so that can add to virus diversity.

00:04:27: These aurobuch viruses are mostly transmitted by midges but also by mosquitoes, although I think the assumption is that main route of transmission to humans through midges.

00:04:41: If you look at history this virus is known for quite a while.

00:04:47: it was first isolated from a sample from a febrile patient in nineteen fifty-five in place called Vega de Oropus.

00:05:00: I think that's a village in Trinidad, so part of Trinitat and Tobago.

00:05:05: And this is where the name comes from.

00:05:08: It was also isolated there by mosquitos, bulls of Mosquitos.

00:05:13: The initial mosquito species it was isolated with was Cogbilletidae when it went to Elanis.

00:05:20: I hope i pronounced right!

00:05:23: That's why they were first found on Trinitate and Tobaco In nineteen sixty, the virus was then found in a sloth.

00:05:31: In northern Brazil and also mosquitos in that area And between nineteen sixty one and nineteen eighty there were spread of the virus in The state of Pará I hope I pronounced it right in north on Brazil and Then between the nineteen eighties and two thousand four There was spread into the Amazon region of Brazil And now the various can be actually found in lots of countries in South and Central America.

00:06:00: Many countries report cases, often it's not many cases.

00:06:05: Reports have been coming from Barbados, Guyana I think also French Guiana, Panama Columbia Ecuador.

00:06:13: but countries that are most affected and report them most cases seem to be Peru Bolivia Brazil.

00:06:21: specifically Brazil has a larger number of cases, and there was also a twenty-twenty four outbreak in Cuba.

00:06:28: And that outbreak seeded a lot of cases in the

00:06:31: U.S.,

00:06:32: in Europe.

00:06:32: so they were a good number of detections travel to Cuba or traveled to other countries that have the virus and then travelled back and got sick at home.

00:06:49: In general, since the nineteen sixties there are about thirty epidemics described with more than half a million reported cases.

00:06:57: but it also has to be said that there's probably a lot of underreporting because the disease is very similar to other diseases that occur in these areas including Seeker dengue infections, chikungunya and so on.

00:07:13: So sometimes it's really hard to distinguish because most of these cases are self-limiting they're not further investigated.

00:07:20: then you can't tell what was a little bit about the biology.

00:07:25: this virus has two cycles.

00:07:28: One cycle is the sylvatic cycle.

00:07:30: This is basically what happens in the rainforest and here you have maintenance of the virus And it's basically bouncing back between mosquitoes and wildlife.

00:07:41: The mosquito species that probably involved in this rain forest cycle are different cullic species.

00:07:48: It seems to be some aedes mosquito species I involve as well, but most of the transmission probably koolicoidas, which is these midges.

00:08:01: And a lot of different wild animals seem to get infected and maintain the virus.

00:08:06: that includes lofts, South American marsupials, primates but it seems also birds can get infected!

00:08:14: Of course when people move around in the rainforest.

00:08:17: this includes tourists, there's a lot of ecotourism in Brazil for example.

00:08:25: They can get infected right they can get bitten and the idea is that it mostly mitches then transmit to humans but people can get bit when they explore these areas.

00:08:36: But also an urban cycle as many viruses are transmitted by mosquitoes And you have transmission from human to this mitchess And the idea is that this really mostly caused by these midges, mostly cullicuidus parenzis.

00:08:55: I think it's the main vector there.

00:08:58: These midges mostly bite during dusk and dawn at least in rain forest but also described as in urban areas.

00:09:06: they start to bite during the day as well.

00:09:10: Most cases actually happen during rainy season which makes sense because probably when more of them are around.

00:09:16: So when people get bitten, the virus starts to replicate and after an incubation time of three or four days first symptoms show.

00:09:25: Symptoms include high fever headache specifically a headache that you kind of feel behind their eyes retroorbital pain muscle pain joint pain And then sometimes also rash and hemorrhagic manifestations.

00:09:43: So sometimes you get bleeding under the skin or bleeding from gums, And interesting thing here is that this disease kind of coming in phases.

00:09:53: so typically there's acute phase that lasts to four days.

00:09:58: then people start feel better.

00:10:00: between day seven and ten symptoms reoccur which is interesting.

00:10:06: In most cases than the disease resolves and in general it's relatively mild.

00:10:12: However, In some cases the virus can be neuroinvasive... ...and can cause meningitis or encephalitis And what is also described as another neurological disease that called Guille-Barré syndrome That not the virus itself doing damage but the virus infection can trigger an all immune response where the immune system then attacks nerve cells.. ..that lead to this Guille Barré Syndrome and sometimes these infections can even lead to death.

00:10:42: What is problematic are infections in pregnant women, this can lead to fetal death but it also leads to congenital abnormalities in the newborns that can include microcephaly.

00:10:57: so this something that Zika virus could do unfortunately But this has been described for oral push-virus.

00:11:03: It's good that the diseases are often mild and self-resolving because there is no treatment for it.

00:11:09: Basically, they're not intervals which can be used or specific treatments like no monoclonal antibodies to use as therapeutic.

00:11:18: There also isn't a vaccine.

00:11:20: And so that means, the only preventive measure one can take to be protected from this virus is mosquito repellence.

00:11:30: To make sure you don't get bitten by long pants or long sleeves and shirts etc.

00:11:37: Maybe mosquito netting when sleeping.

00:11:40: but there's no other way to protect yourself from these midges... ...and mosquitoes!

00:11:48: And that was it about our bush virus.

00:11:51: That's, there was the third episode in our series of viruses that are transmitted by mosquitoes and other biting insects can infect you during your summer vacation.

00:12:03: I guess we'll continue with more viruses next week but In meantime if have any questions concerns or comments feel free to write an email to Virological at podcastwerkstatt.com And if you like the podcast and want to support it, do that on Steady.

00:12:20: Thanks for listening in!

00:12:22: Until next week –

00:12:37: bye!