#8 – Nipah Virus: If It Mutates, It Could Become A Pandemic Threat

00:00:05: If it becomes more efficient in spreading, this could be a big issue because then you have a virus that efficiently jumps from humans to humans through the air which means its hard to stop.

00:00:16: In addition to that this virus is super deadly and would really bad combination.

00:00:33: Virological with Florian Kramer.

00:00:46: Hello and welcome into today's episode of ViroLogical.

00:00:50: This was recorded on March thirtieth of twenty-twenty six in New York.

00:00:55: So today we're going to talk about Nipah virus.

00:00:59: That's a very interesting and very deadly virus, And honestly that really kind of my nightmare virus in the way... ...and you will see why it again badly might be to some extent human to humans transmissible at some point.

00:01:17: new date become new pandemic.

00:01:21: so Let's talk a little bit about this virus.

00:01:24: Nipah viruses belong to the Hennepa Viruses, basically they're a mix of virus that is distantly related to viruses like measles or mums.

00:01:37: It has negative sense single-stranded RNA genome.

00:01:41: What does it mean?

00:01:42: Negative sense just means that genome needs to be transcribed by polymerase into positive strand RNA before proteins can be translated from it.

00:01:57: When we look at the virion structure, RNA genome on the inside that's covered by a nuclear protein, and it protects their RNA genome.

00:02:07: There is an associated polymerase in the phosphobrotein And then we have matrix proteins which stabilizes the virion from the inside.

00:02:14: Then there are lipid membranes.

00:02:17: In this lipid membrane you get two glycoproteins or spike-proteins.

00:02:21: One is actually called G or glycoprotene That attaches to our cells.

00:02:27: We also have another one called F or fusion protein, and that's the one that causes fusion of the viral membrane with the membrane of our cells so that the genome can get into ourselves.

00:02:41: And actually this Nipah virus... The fusion happens on the surface not like many other viruses.

00:02:49: after the virus would be taking up into tiny vesicles called endosomes on the cell surface.

00:03:03: A little bit more about the virus structure and how it looks like, these viruses are about a hundred fifty nanometers in diameter.

00:03:11: they're kind of roundish not really round but kind-of round shaped.

00:03:17: we call this pleomorphic.

00:03:19: In my opinion Nipah virus particles look pretty ugly.

00:03:25: That's just my personal opinion, I like influenza viruses.

00:03:28: They look much nicer.

00:03:29: but yeah again that is a personal preference.

00:03:33: So we have these two spike proteins the G and F protein And the G-protein.

00:03:39: as i said it binds to our cells.

00:03:41: It does this by interacting with proteins on ourselves Two specific proteins effrin BII and effrinBIII.

00:03:55: FNB-III is in humans found cells in our brain and the virus that infects brain cells, it's never a good thing.

00:04:06: And FNP-II is expressed many of our body but also in their airways.

00:04:12: That' s not another good thing because they would suggest that the virus can replicate on the upper and lower respiratory tract which helps viruses typically to spread faster.

00:04:25: So where does this virus come from?

00:04:27: What's the history.

00:04:28: It was first detected in September of nineteen ninety eight, In the western part of Malaysia.

00:04:34: there was an outbreak in pigs and humans.

00:04:38: initially The pigs were infected they had respiratory symptoms And then the virus jumped over into humans.

00:04:45: Humans had a different type of disease.

00:04:47: It was more like ancephalitic disease, so brain infections basically.

00:04:51: but we'll get into the disease phenotype little bit later.

00:04:55: and initial outbreak led to about fifteen deaths in humans And it really wasn't clear what kind of pathogen or viruses causing these infections.

00:05:06: initially people thought maybe Japanese Bencephalitis which can also you know, get amplified in pigs and then jump into humans.

00:05:14: But that usually happens via a vector or via mosquitoes which wasn't the case here And this outbreak started to spread including an area next to the Nipah River in Malaysia where their name comes from.

00:05:32: This outbreak grew relatively large.

00:05:34: In the end there were two hundred sixty-five human infected and one hundred five of them died.

00:05:40: So that means the device has a relatively high case fidelity rate.

00:05:44: Malaysia is growing a lot of pigs and then exports them into Singapore, so Singapore's right next to Malaysia it basically this little part on bottom of Malaysia On an island.

00:05:57: And there were also eleven cases in slaughterhouses, slaughterhouse workers In Singapore at one death.

00:06:07: You know, we are used to having these viruses identified pretty quickly as you have seen with SARS-CoV-II where a very short period of time after the outbreak starts.

00:06:16: We know what's causing it but this is more than twenty five years ago and back then basically from September of nineteen ninety eight till March of nineteen nineteen nine do identify the virus that caused the outbreak and was identified.

00:06:36: People also figured out relatively quickly that the virus was originating from bats, that it was circulating in bats and In this case really large bats.

00:06:46: They actually called mega-bats.

00:06:48: This case is flying foxes And the virus were associated with two species of Flying Foxes Theropus vampiros That's a large flying fox and theropos hypermelanos which are small flying fox.

00:07:03: bats eat fruits and the problem was that in a lot of these big farms, there were fruit trees.

00:07:13: And bats are coming in when they're eating their food on the tree.

00:07:18: They're pretty messy eater so... ...a lot of the fruit that's chewing on falls down that is contaminated with saliva.. ..and if they hang it in this tree probably also... urinate and the feces might fall down.

00:07:33: And then if there are pigs below these trees or close to this tree, the pigs may feed on these bits of fruits that fall down that are contaminated.

00:07:41: they also come in contact with urinal faeces.

00:07:45: That's how they can get infected.

00:07:47: as I mentioned initially in Malaysia the disease spread from pigs to humans.

00:07:53: Big farming was then restricted in some of these areas in Malaysia and in a way that took care of the issue.

00:07:59: So basically human infections, I think also pig infections disappeared in Malaysia although retrospective studies identified.

00:08:09: there probably have been earlier outbreaks in this area going back to nineteen ninety six but the virus resurfaced in two thousand one different countries in Bangladesh.

00:08:22: the way how people get infected there is different and it's also pretty interesting.

00:08:27: So, that not a lot of pig farming in Bangladesh but what people are doing.

00:08:32: they harvest balm sap.

00:08:35: so basically people climb up into palm trees specific balms that produce sugary fluid or sugary sap if you cut them.

00:08:44: So you climb up into the tree, cut it and put a container there to collect the sap.

00:08:51: The juice that comes out of this tree is tasting sweet!

00:08:56: And people leave their container overnight so they can accumulate the juice.

00:09:02: It's not only humans who like the juice but these flying foxes too.

00:09:09: They basically drink from those containers.

00:09:11: They contaminate the bomb sap with their saliva and with that with the virus.

00:09:18: And, this leads then to outbreaks in humans when they drink these raw bomb sap that has been harvested.

00:09:26: These outbreak are relatively frequent.

00:09:28: in Bangladesh there was one in two thousand three, two thousand four ,two thousand five, two hundred eight ... two thousand eleven... two thousand eighteen.. two thousand nineteen ..and so on and so forth.

00:09:37: So you get it!

00:09:39: There's relatively frequent detections of human infections with these viruses.

00:09:45: And sometimes this can be up to fifty individuals, so it's a little bit larger outbreaks not always just the few cases and in recent years we have also seen smaller outbreaks in India for example in Kerala.

00:09:59: even in twenty-six there was an outbreak in West Bengal.

00:10:05: The case fatality rate in a lot of these outbreaks is very high.

00:10:09: It's often between fifty to seventy-five percent, sometimes even as high as ninety percent and that's of course very concerning.

00:10:17: So little bit about the disease, the incubation time is between three to fourteen days.

00:10:24: Some rare cases it can be longer I think upto forty five days has been reported And the disease starts with relatively unspecific symptoms similar to actually an influenza infection.

00:10:39: Fever, headache coughs, sore throat.

00:10:42: so the respiratory tract is involved people get muscle aches sometimes vomiting is involved and then over time unfortunately virus reaches central nervous system And then people develop neurological science that are indicative of acute encephalitis.

00:11:00: So acute brain infection.

00:11:03: People might then fall into a coma and die.

00:11:07: But there can also be severe respiratory distress, not just the upper respiratory symptoms that I mentioned earlier.

00:11:14: And as i mentioned A lot of people who get infected actually die.

00:11:18: so The case fidelity rates are very high.

00:11:22: If people survive their infection There often long lasting consequences, persistent convulsions for example.

00:11:29: but Even personality changes have been reported.

00:11:32: and that's probably because, you know people get infections in their brain.

00:11:36: What is bad here?

00:11:37: Is this combination of the virus ability to infect a respiratory tract... ...and to infect the brain.

00:11:44: Infecting the brain means like with rabies for example.. ..that the outcome for the patient is not good.

00:11:51: those infections can be very deadly.

00:11:54: In fact, the respiratory tract is also bad because that means that the virus potentially can spread via the air.

00:12:01: Via droplets or aerosols and so it's known that Nipah viruses actually can spread from humans to humans.

00:12:11: That has been described.

00:12:12: in Bangladesh There were clusters where one person infected another person And there was an analysis done of cases between two thousand one and two thousand seven that found the R-naught for NIPA virus is zero point five.

00:12:27: Now what's the r-naut?

00:12:29: We discussed it in one of the initial episodes, there are not describes how many people one infected person will infect.

00:12:37: so if they're not this one the virus keeps circulating in their population.

00:12:41: because when a person always infects another person you know infection change keep going If The R-nought Is Below One.

00:12:50: So In This Case With NIPAA The estimate was zero point five.

00:12:54: That means there is some spread but the spread stops by itself and that's good, the virus not very infectious But it can jump from humans to humans And I think the fear Is at a time when It might mutate or learn To do better If becomes more efficient in spreading.

00:13:14: This could be big issue Because then you have a virus that efficiently jumps From human through air which means it's hard to stop.

00:13:22: In addition, this virus is super deadly and that would be really a bad combination.

00:13:27: so... A pandemic with respiratory virus was the case for the allergy rate between fifty- and ninety percent will truly be disaster.

00:13:36: And because of that there are actually lots of vaccine development for NIPA lot movement There.

00:13:43: one technology used is vectored vaccines.

00:13:49: For example, that's the same vector used for AstraZeneca vaccine during SARS-CoV-II pandemic.

00:13:55: I think they now have a Nipah vaccine in phase two.

00:13:58: then vesicular stomatitis virus vectors are used to develop Nipa vaccines.

00:14:04: That is the same Vector system which was used for Ebola vaccine development successfully because we currently have an Ebola vaccine based on this vector.

00:14:16: And then there's also a number of other approaches in clinical trials, including mRNA vaccines against NIPA.

00:14:23: A lot of that is in phase one or phase two and it would actually be very hard to get these vaccines licensed because with this infrequent outbreaks It wouldn't be possible really do efficacy studies and see how well the vaccine protects.

00:14:40: But it's important to get these vaccines ready in case they are needed for a smaller outbreak or even the larger outbreak, for pandemic preparedness.

00:14:49: In addition to vaccines there is also monoclonal antibodies that are in development of treatment and prevention of these infections.

00:14:58: One of this antibody is called M- one oh two dot four.

00:15:01: That has already been compassionately used.

00:15:07: but there is also more of these antibodies in development and having monoclonal antibody therapeutics for Nipah virus, related viruses would be very important.

00:15:19: Since we are talking about related viruses There's actually a similar virus that circulates in Australia Also in flying foxes, Australia has Flying Foxes too And this virus called Hendra virus.

00:15:30: It's closely related to Nipa virus.

00:15:33: In this case, the virus infects mostly horses and then it can jump from horses to humans.

00:15:39: in This case a vaccine has been developed for horses And that has taken care of a lot of problems with handraviruses in Australia.

00:15:47: But I think its easier to vaccinate horses than flying foxes in Bangladesh.

00:15:52: but... ...this is also where name of group of viruses comes from Hennepa virus or Hennipa Viruses.

00:16:00: It's basically combination Hendra virus and Nipah virus, so Henipa virus.

00:16:06: And that's where they are called like that.

00:16:09: People are discovering more and more similar viruses.

00:16:12: That related to nipah viruses and hendra viruses.

00:16:16: The latest example is a virus that was discovered in Shrews In Alabama.

00:16:22: It's called Camp Hill Virus.

00:16:24: I think it wasn't the news about a year ago.

00:16:27: Its not clear if that virus can infect humans if it has actually any potential to cause disease in humans, but its good know that is around and maybe a good idea.

00:16:38: stay away from shrews anyways.

00:16:41: What's also worth mentioning?

00:16:44: this Nipah virus outbreak in Malaysia with the pigs was the basis for movie came out in two thousand eleven The movies called Contagion.

00:16:53: It really worth watching super interesting Specifically now after going through this SARS-CoV-II pandemic, there's a lot of parallels in that movie.

00:17:04: It really maybe not entertaining but an interesting movie to watch.

00:17:09: I remember when the movie came out.

00:17:12: it was at Bostock Monsignor and Peter Belize's lab And Peter also was chair here And he decided to rent a movie theater, I think on the west side of Manhattan and take out the whole department to watch the movie.

00:17:27: So we all went there and watched the movie... ...and it was amazing!

00:17:31: But Peter actually complained afterwards that it wasn't a Hollywood movie at all.

00:17:36: There were no love stories in there.

00:17:38: It wasn't very entertaining and too realistic for an entertaining film so that kind stuck with me.

00:17:46: but i can really recommend watching.

00:17:49: All right, with that to summarize, Nipah virus is a virus that circulates in flying foxes.

00:17:55: In Southeast Asia it sometimes infects humans through different ways either through infections of pigs and then it jumps from pigs to humans or through consumption off this bomb sap in Bangladesh probably consumption of fruits in India.

00:18:12: It's relatively deadly...it has limited capacity to spread from human to humans And there are vaccines and antibody therapeutics in development, but it's really one of the viruses that I watch out for because this combination of infecting the respiratory tract being capable of limited human-to-human transmission.

00:18:35: Its ability to infect a brain and be super deadly is something that's problematic.

00:18:40: if the virus becomes... better adapted to humans and starts to spread from humans more efficiently, this could cause a really bad pandemic.

00:18:49: All right that's it for today.

00:18:51: as always if you have any questions comments suggestions please just write an email to Virological at podcastworkstud.com And If You Like This Podcast Feel Free To Support It On Steady.

00:19:05: Thanks Until Next Time.

00:19:08: Bye.

00:19:11: If you're enjoying the podcast and would like to support our work, visit us on Steady.

00:19:16: You'll find a link in the show notes And don't forget to follow & leave a review of your favorite podcast app Podcastwerkstatt.