[Music] What is known is that this leads to elevated ocular pressure, so basically high-apression DI, and that can lead to irreversible damage of the optical nerve, and in the long run can lead to severe vision impairment. So not a good thing to have. [Music] Biological with Florian cream. [Music] Hello and welcome to this week's episode of our logical. This was recorded on April 26th, 2026. In New York. And today we're talking about very crazy story about new human pathogen. I'm newly discovered human pathogen. Actually, the pathogen was known, but it wasn't created, it would cause disease in humans. And this pathogen, this virus is called Covered Martiality Noader Virus, or a CMNV. The story here really is that this is the first virus that can jump from crustaceans, basically shrimps, or fish, to humans. So this virus infects all kinds of crustaceans, fish, and it was known as a problem there, and they'll get to that in a few minutes. But now it became clear that it can also cause disease in humans. So this CMNV is a no-divirus. No-divirus is actually known for quite some time. The first one was discovered in 1956 in a mosquito, a Kulex mosquito, in a village in Japan and the village's name is No-da-mura, and that's where the name is coming from. We do know that there's two different types of no-da-virus, alpha-no-da-virus, and beta-no-da-virus. The alpha-no-da-virus are known to infect insects, and the beta-no-da-virus are known to infect fish. These viruses have positive sense single-stranded RNA genome that holds for approximately 4,500 no-killed diets, so basically the genome has about 4,500 letters. And the interesting part here is that this is actually segmented virus. It has two segments. So it's similar to influenza virus, influenza virus in that respect. In influenza viruses have 8 or influenza CNT viruses have 7 segments, and here we have 2 segments. And the first segment is called RNA1, and that encodes the polymerase, and the B-brotene that counteracts immune responses in the host cells. And then the second segment is called RNA2, and that codes for the capsid. It's a very simple virus, actually. It's approximately 29 to 35 nanometers in diameter. It doesn't have a lipid envelope, it only has the capsid. And the capsid has a very nice structure, symmetric structure. Three of these capsids come together to form a three-fold symmetry, and then this whole thing assembles into the virus particle. And in the end you have 180 copies of capsid bird particle. The virus is also very stable. It's pH stable between pH 2 and pH 9. It's also relatively temperature stable, and it replicates in the cytoplasm. We know about neurovirus, but what's special about this covert mortality neurovirus. So in 2009, problems appeared in Chinese shrink farms. Basically, in some instances, part of the population that they had in the shrink farms died off, off not the full population, just a percentage. And it became clear that this was specifically a problem with the temperature, was rising above 28 degrees Celsius. But there was not so much of an issue at cooler temperatures. And so this was investigated in 2014. The bettogen that caused this disease, this die-offs, was isolated, and characterized, and it turned out that this was a notavirus, and it was called covert mortality notavirus. And in 2016, the same virus was also identified in Thailand, and I think now it's found worldwide in agriculture, but also in wild called seafood and fish. The idea is that the original version of the virus is actually coming from a critical, Arctic krill. Those are also crustaceans that live in Arctic waters, basically look a little bit like small shrimp. And the idea is that the virus originally came from these animals. As I mentioned, the virus infects fish, crustaceans, and Hino terms, which are basically sea urchins, for example, similar creatures. It's not only causing disease in shrimp, but also in fish, often farmed fish when they're infected. They don't feed much, and they also start to swim in a very uncoordinated way. So again, this can be a pretty big problem in aquaculture. But for a long time, the idea was, okay, this is a shrimp and fish, the virus, it's not necessarily an issue for people consuming infected animals. But in 2019, a new disease was characterized. And so the idea was, okay, this virus is a problem in fish. This virus is a problem in crustaceans, but it's not a problem for humans. So in 2019, a new disease was detected and characterized in China, and the name of this disease is quite long and complicated. It was during persistent ocular hypertensive viral anterior UVitis. I also had to look up a lot of these words. Basically, persistent is here. It's kind of long term, right? Occular just means eye, right? Hypertensive means that pressure is higher. Viral is clear. Anterior just means in front. And UVitis basically means inflammation of the uvia, which is one of the three layers of the eye. And the uvia has actually three components. The iris, the cilia body and the coruid. And with this persistent ocular hypertensive viral anterior UVitis, or for short, B-O-H-V-A-U, mostly the iris is affected and inflamed. And I guess that's why it's called anterior, because the iris is in front of the cilia body and the coruid. And so that's anterior. That's in front. And it's known that uviaitis can be caused by many different viruses, but also other pathogens. For viruses, most often it's caused by cytomegalovirus, or hyposimplex virus, or hyposviruses. But this new form of the disease wasn't associated with any of these other pathogens that are known to cause uviaitis. You know, people looked at typically these cases tested negative for other viruses, or better genes that can cause uviaitis. But what is known is that this P-O-H-V-A-U, so this new uviaitis syndrome leads to elevated ocular pressure, so basically higher pressure in the eye, and that can lead to irreversible damage of the optical nerve. Also, corneal and dutelial loss, the iris can be damaged, and in the long run can lead to severe vision impairment. So not a good thing to have, but this can be treated, and typically the symptoms get better when it's treated. Another thing that was recognized is that this often affects all the people, which is also interesting. And so this was first recognized in 2019, that there's a new form of uviaitis, and now in March of 2026, so basically a few weeks ago, paper came out in nature microbiology, so that's a challenge that's published by the Nature Group, and the study was performed by a number of state key laboratories in China, also the China Center for Disease Control, and you can use in Singapore was also involved with this study. What did they do? They wanted to really get to the bottom of this and find out what was causing this new disease, and so they acquired iris tissue from patients who had the disease, and first looked by electron microscopy and they identified virus particles, actually a lot of virus particles in that tissue, and this virus particle,
particles looked like nodal viruses. They also performed sequencing and developed a PCR for the virus. And it turned out that you could find the genome of the virus in the iris tissue, but also in plots of infected patients. And the interesting part was that they could also see that antibodies developed against these nodal virus in these infected individuals. And when the sequence devirus, it had 98.96% identity. And when the sequence devirus, it had 98.96% similarity to this covert mortality nodal viruses that circulated in aquaculture in China. They went further. They also wanted to basically prove that these viruses could infect mammals and could cause this disease. So basically, they were trying to fulfill coaxbostulates. And so they infected mice and the mice got infected and actually developed issues with their eyes. So basically also high pressure, high ocular pressure. And so they could basically show that the virus does cause this disease in mammals. They also wanted to look at how prevalent the virus actually is. And so they went and got samples from markets, but 350 samples. And they found that approximately 55% of fish samples were positive for this virus, but 28% of shrimp samples, 62% of crab samples, 59% of mollusks that are disempled, and 47% of samples from octopus and squid and so on and so forth. That doesn't mean that prevalence is really that high. Could of course be when you know, at seafood markets, when fish are processed, when animals are processed, the death cross contaminations. So maybe some animals have a lot of the virus. And then other ones just get contaminated with this. And they actually don't carry the virus. But still, the number is relatively high. It seems that this virus is relatively prevalent in food items. They also looked at distribution from where these different samples came from. And they found that 36% of the samples they got from products from Antarctica were positive. At 20% of African products were positive, 16% of American products were positive, so meaning North and South America. And then 60% of Asian products were positive. So the virus seems to be around quite a bit, and it seems people get exposed to it through food on a regular basis if you consume fish and seafood. And so they also looked on an epidemiological site what the risk factors would be for getting this disease and for becoming positive for this covert mortality nodal virus. And they found that the number one risk factor was basically work with fish and seafood, processing of fish and seafood, specifically when people had little cuts or injuries. For example, when they worked with fish, fish often very spiny. Their scales can be relatively sharp. So you get this little injuries. And that seems to be associated with getting infected, with this new nodal virus. What also was a risk factor was eating raw seafood and raw fish. So that's bad news for people who like sushi, like me. And another risk factor was to in general have contact with fish, crustaceans, or work at aquaculture or in the fishing industry. So this is super cool. Of course, a lot of confirmation is needed. This was the first study that made this connection between covert mortality nodal virus and this new ocular, this new IDCs in China. I don't think this new disease has been diagnosed anywhere outside China so far. And it's also, as I said, new. They started to detect, to see that in 2019. So I believe a number of additional studies have to be performed to really confirm these findings. But it's super interesting that a virus seems to be able to jump from crustaceans and fish into humans and cause disease there. That's the first time something like that has really been reported. And I'm super interested in that because I also work on influenza viruses that infect fish. And it's completely unclear if they can cause disease in humans there, of course, not like regular influenza viruses. So it's a super interesting topic. And we'll see if there's more work in that regard coming out and what the countermeasures will be to avoid these infections. So thanks for listening in. As always, if you have any questions, comments, concerns, please just send an email to
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