Episdoe 72: Bird Flu with David Engelthaler, Ph.D.

Karie Dozer [00:00:04] I'm Karie Dozer and this is TGen Talks. Bird flu or avian influenza is a contagious disease caused by strains of the influenza, a virus that typically affects birds. While it's rare and easily treated in humans, it's also easily spread. And public health officials and animal health officials must work closely to monitor any outbreaks. Reports of bird flu in agricultural settings earlier this year caused the CDC to respond with warnings to at risk individuals. In this episode, we'll talk about just who does and who does not need to worry about the virus, and how scientists at TGen are keeping a close eye on the virus and how it's changing. So this episode of TGen Talks brings us once again to TGen North, and our guest is Doctor David Engelthaler, and we're talking bird flu. We've been seeing a few headlines about it. What do we need to know.

Dr. David Engelthaler [00:00:54] Yeah. Great to be here with you, Karie. You know, bird flu is like all other influenza viruses. Continues to change and mutate gradually and then sometimes all at once. We're concerned about this particular strain because it's called H5n1. We know that this particular strain can be really virulent if it gets into humans, but it doesn't seem to transmit between humans. It's been around for probably close to 20 years, and it hasn't been causing real problems in us. But now all of a sudden, it has really spread around the globe, causing lots of deaths and birds spilling over into mammals. And we're starting to see a few human cases, not very serious cases, but it is showing up. So it's, it's something that we're really keeping a close watch. 

Karie Dozer [00:01:41] On what happens to humans when we contract bird. 

Dr. David Engelthaler [00:01:43] Flu. So what's really interesting, the strains that were circulating in Asia about ten years or so ago, actually would look like a very serious flu infection that would rapidly cause a very serious illness that ended up killing about 50% of the people that were infected. So incredibly virulent. But we never saw it spread from human to human. What we're seeing now with this strain that has spread around the globe, especially in North America, in birds, humans, there's been a few human cases. And what's really interesting is that most of them just show up with really bloodshot eyes. So they get this conjunctivitis, really red eyes, and it doesn't seem to go beyond that very mild respiratory, if anything. 

Karie Dozer [00:02:28] Who notices an outbreak first? Where does it pop up?

Dr. David Engelthaler [00:02:32] In the US we had been seeing, especially over the last two years, how it's really spread in wild birds, and there would be bird die offs and, you know, wildlife managers or even in places like zoos would see birds dying off for some reason unknown. And then they test it and they find it's an influenza, and then they find out what kind of an influenza virus it is. We also had some instances where it was showing up in poultry houses, and then you'd have these die offs in poultry chickens, and then the same kind of thing, you go and test and then you track it down. You see it's an influenza strain. So that's how we typically see it. What's also interesting, though, is that we've been having, wild mammals found dead, and they usually get tested for things like rabies or West Nile virus, but they're being tested and being found positive for this bird flu. And that's most likely because the most of them are carnivores that we find, and they're eating birds that have died or got sick from flu and they're easy to catch, and then they get it themselves and died. And so it's just kind of looking at these strange occurrences and then going and doing further testing.

Karie Dozer [00:03:40] Is that how the virus would jump from animal to human? Do we have to consume the sick animal?

Dr. David Engelthaler [00:03:45] Yeah, that's actually a concern. Is would we get it from consuming wild animal, or we can talk about cattle in a second. Infected milk? Most likely not, because we cook our food while the animals don't cook their food. And so the virus is actually easily destroyed, especially with high heat temperatures, pasteurization of milk, etc.. So that's not a big risk for us, but it's being in close contact and handling it, probably. We know that it's shed in in feces. It also respiratory secretions for some animals. So in birdhouses we there's been a number of human cases in Asia associated with poultry handling. And it's usually it's probably in the feces. You get up in the air and then you breathe it in. But maybe with mammals, especially with cattle, that might be the respiratory secretions, because cattle have a lot, and they secrete out a lot of virus. And then if you're not using proper hygiene and bio, safety measures, you could get into your eyes or your nose, and then that's how you would be infected. 

Karie Dozer [00:04:46] So if you're not working on a cattle farm or at a poultry farm, it's probably this probably isn't something to be worried about. But what is the agriculture world doing to keep a handle on it and make sure that it's not getting out of control? 

Dr. David Engelthaler [00:04:59] Yeah, on that first part, you're right. It's an. Absolute, very low risk of illness for the general population. We don't want people thinking that this is now we're in some kind of pre-pandemic phase right now. The risk is to the agricultural workers. And so there's a lot of communication that's happening with the USDA and FDA and CDC to various agriculture workers on how best to handle animals. What are the precautions to take, especially if you have a positive animal, a bird showing up in in in your system, what do you need to do and what are the steps that need to be taken? And so there's a lot of PPE that needs to be worn the gloves, the gowns, the N-95 masks, everything we talked about during Covid is actually becoming really useful for these agriculture workers.

Karie Dozer [00:05:46] What about just experiencing wildlife? We're in Flagstaff now and everybody's out hiking. I mean, is that something to be more aware of? We come in contact with birds all the time.

Dr. David Engelthaler [00:05:56] Birds and other animals that may look sick. What we just don't want to do is ever handle dead or sickly animals. If they're near people, it's definitely best to call county animal control. They can assess, potentially get the animal taken in for testing. And that happens quite a bit. Really interestingly, there's been one mammal in all of Arizona that's tested positive for H5n1, and that was an Abbott's tree squirrel. We have no idea how it got it. It's very, very interesting that a squirrel would get it. And it was probably seen because the squirrel was either dead or was getting really sick, and then, was either going to go into like an animal rehab facility. But then it was, had died and they tested it and tested positive. I guess the point is, if we see something like a, a dead or a sick squirrel and it tests positive, that means there's probably a whole lot of other activity that's happening in the background that we don't see. We don't see most animals, especially wildly, animals that die. And so when we do find one, then we just know, well, it's already present. That means that we do need to take these precautions. So for the general population, that might be the biggest risk is coming in contact with a sick or dying animal or dead animal, and you just don't handle those. And if you need to, you have to use those precautions. Lots of information on the on the CDC website. But again, gloves and gowns and things like that.

Karie Dozer [00:07:20] What is Jen doing to help monitor the situation? And I guess stay on top of it in case there is a need to sort of play defense.

Dr. David Engelthaler [00:07:28] Very interestingly that we're seeing that this virus, like so many of the other things that we're monitoring now, can show up in wastewater. So that's actually going to be a really great monitoring tool to see if it does start showing up in. People will be able to find that because we're already monitoring wastewater around the country. And Jen is helping to do that right here in Arizona. So we're on the lookout for that. We can we certainly can test for this virus. We are doing other wildlife studies as well as companion animal studies. And right now we're going to be applying our influenza assays to those studies to see are we seeing it pop up again? We're not seeing this as the biggest threat out there. But what we have to do is get better eyes on this, develop better Intel on the situation.

Karie Dozer [00:08:15] What about pets? Squirrels aren't an animal that most people would keep as a pet. How dangerous is bird flu for my dog. My cat. An animal that's sharing my home.

Dr. David Engelthaler [00:08:24] Yeah, we've seen interestingly, at the infected, cattle lots in in different farms that there's been a number of positive cats. It's not been fully traced down yet, but it's quite likely that they're being fed contaminated milk because it's not pasteurized on the farm. And that's how they, you know, typically feed your barn cats and whatnot. You put out milk and they're getting it. But we've also found is that there are infected mice on these farms, mice, you know, they'll get into all sorts of gross things, and they could get infected. The cats eat them. We're not really sure how the cats are getting infected. Not a lot of information right now about dogs.

Karie Dozer [00:09:02] What makes it come and go? I mean, simply put, what makes an outbreak go away? And what makes one start up again?

Dr. David Engelthaler [00:09:09] Yeah, thinking about Covid. We used to talk about those different mutations in the spike protein. And when we get a whole bunch of them, then we'd have a new variant because it'd be really different than the last one. So we would call it Omicron or Delta or the like in influenza. What we look at is influenza really has two different types of spike proteins. Those are called those are really the H protein in the N protein. So when we talk about H5n1 that's really the variant. And so those proteins can actually change through just some random mutations or change just a little bit. And that's what we're seeing right now with H5n1 seems to be changing just a little bit. And now it's spread really rapidly in birds across North America and now spilling into different mammals. But when we actually get an H changing or an N changing, that can actually drastically alter, so that really becomes a. New variant type. And so in about mid-June, there was a patient in Mexico who didn't have contact with any animals that's known. He developed a infection with H5 and two. So a new it's still classified as a bird flu strain. And that was actually very serious. It was a fatality. We haven't seen any other cases from that. But that was unexpected. We hadn't seen H5 into spreading around. So what actually happens with influenza? And this is, this is the. It's really interesting, but fairly scary in that flu has a way of if you get infected with two flu strains, it can develop a Frankenstein version of the virus of those two different strains really easily. And then you could have something that could either be more easily spread, maybe less easily spread, but more virulent. That's how we get these really big changes. When you get this mixing inside of not just people, but interestingly enough, birds as well as pigs. Pigs are like a mixing vessel. They can get infected with pig flu, human flu, and bird flu.

Karie Dozer [00:11:04] All at the same time, all.

Dr. David Engelthaler [00:11:05] At the same time. And in fact, this happened in 2009. If you remember, the swine flu pandemic is a real pandemic, the first real pandemic of the millennium. That was a mixing of three different viruses, most likely in a pig and a farm in Mexico. And then within a matter of weeks, it spread around the world. So these things can happen. What we're most concerned about with bird flu is that these H5 bird flus can be very fatal to humans in some cases. We just got to hope it doesn't start spreading between people.

Karie Dozer [00:11:35] Do these different viruses, do they behave similarly? Even if they're different? They have a different makeup. Do they act the same? Do they change at the same rate? Is there a certain level of predictability that you have? Once you've looked at one virus, you can kind of predict another.

Dr. David Engelthaler [00:11:49] The only predictability is that we know that will continue to change. We can put a little bit of a molecular clock to understand how many mutations the virus will pick up, and kind of estimate how many in the most important places, like on those spike, those outer proteins. But what we can't do is predict when two viruses come together and mix and mingle and then have an offspring, that is something that's more dangerous. And so it's that can be more like a black swan event. We can't predict it. And then all of a sudden it becomes something really bad. And in this case, it’s really a giant pandemic among birds has been hundreds of millions of birds have died of bird flu over the last several years. And we're seeing, you know, really high numbers of poultry being wiped out. And so that's a huge impact on the economy as well, especially for the agriculture sector. Now we're seeing a large number of cattle being infected, but it doesn't seem to be very serious. It does have real impacts economically in ways that we couldn't predict until it really shows up and starts infecting different animals.

Karie Dozer [00:12:53] Can the animals be treated so that they recover, and they're no longer sick and don't produce bad milk or.

Dr. David Engelthaler [00:12:58] Yeah, here's the great news is that we actually already have existing vaccines for H5n1. We know that. And they're being used in agriculture. So certainly to prevent infections in both birds and in mammals. And there are antiviral drugs that are out there. You can go in and get Tamiflu, right. If you have influenza. They seem to work right now really well against the circulating strains. So we already have a whole bunch of stuff ready to roll out if it ever does become something more serious. So that's great news. 

Karie Dozer [00:13:31] So we just went through Covid. I mean, we're still in some senses in it, but most people would consider that pandemic over. What does something like that do to the public, the population and our attitude about something like bird flu. Does it make us better prepared, or does it make us fatigued and we don't want to hear about it?

Dr. David Engelthaler [00:13:51] You know, I unfortunately, I think coming out of the pandemic, we're fatigued and we're really far apart from each other as opposed to coming together to respond to things like this. Right. There's all this polarization and the politics that came into all of that. That's going to make it very hard to respond during the next pandemic. If it happens any time soon, you know, hopefully not. Hopefully we don't see it. I don't feel like we're a lot better off to respond as people and as communities, but we do have a lot of tools and technologies that we can get out there, roll out the really fast to help prevent the worst of a of a really bad flu pandemic. Now, saying that we actually see flu every year, right? We always have the seasonal flu. And for most people you suffer through it. If you get it, you might be on your back for a week. And that's awful. But it's not the worst thing in the world. But we also have about 30 to 40,000 people die every year from influenza. So these infectious diseases are important. And whether it's a pandemic or not, there are things that we still can do to protect ourselves and protect our families and protect our loved ones. 

Karie Dozer [00:14:55] Are we better educated about something like bird flu having gone through Covid? I mean, do you feel like most people? Know a little bit more whether or not they're receptive to the message and they're going to do anything about it.

Dr. David Engelthaler [00:15:06] It's a good question. I think some people are much more in tune. Right? I think some people have really understood that, you know, infectious diseases are things that are going to be around us, and there's things we can do about them. We shouldn't just say, well, you know, it's out there and I'll get it. If I get it, we can actually prevent those things or treat those things better. Most importantly, we can prevent the, the most at risk, or at least limit their overall exposure by protecting them. In a case like influenza, we definitely still recommend seasonal vaccinations. They're not perfect. We shouldn't pretend that they are, but they're also very safe, have been used for very long periods of time. And we do know they reduce the overall risk of getting a serious illness. And that's most important for people over 65 or for very young children.

Karie Dozer [00:15:53] What have I missed? Is there anything you want people to know that I failed to ask about? 

Dr. David Engelthaler [00:15:58] You know, someone asked me if, you know, with infectious diseases, what keeps you awake at night. And honestly, none of these really keep me awake at night. But if one did, it would be a bird flu. That actually does essentially become something that's easy to transmit between humans. And it's as virulent as what we were seeing in in Asia. That is something we are not prepared for. And it and hopefully it becomes again, a wakeup call of really there are things out there much, much worse than Covid. We really got lucky with Covid. This thing is not worse than Covid at this point. In fact, it's much more innocuous to humans anyways. But it could become something worse or there is something still out there that could happen. And it's not to be afraid, and it's not to stay awake at night, but it's a, it's a, it's a reminder that we really do have a lot of work to do to be prepared for the next one. So we should be thinking about that. And, you know, we talked a lot during Covid about gain of function research. And what do we what happens when we monkey around with these viruses in the lab and make them worse? Is that going to spill over? We know absolutely with influenza mother nature is always doing gain of function research. It is constantly changing. And there's constantly this roll of the dice. And by and large, most of the time nothing bad happens. But we do have to be prepared for when something does happen. So we can't just say COVID's over, let's just go back to being normal. What we should do is say, how can we be better prepared for the next one?

Karie Dozer [00:17:30] Are there tests for bird flu? And is that something that we would have to step up should this spread? Covid tests weren't readily available quickly. We had to catch up.

Dr. David Engelthaler [00:17:39] Yeah, well, and in fact, places like TGen were way out ahead of most places and TGen had the first test available in Arizona for testing that wasn't the CDC test. That was problematic, right? And so there's a lot of labs like TGen and us included that have developed H5n1 testing capability, so we can respond. But, you know, we always have this kind of threat of the federal government regulatory side, the FDA and others saying, no, this all needs to be controlled and run through government approved labs or whatever that is. That could be a risk. And I think we've got to get past that. We've got to be able to say, we're all in. Let's use the great resources and talent that we have to be able to respond. So there is testing some testing capability out there. We're not ready to start testing millions of people. And thank goodness we don't have to right now. 

Karie Dozer [00:18:31] The CDC should come to TGen. You guys are really good at doing it quickly. Thanks for your time.

Dr. David Engelthaler [00:18:37] Yeah. Great to be here, Karie.

Karie Dozer [00:18:39] For more on TGen’s research, go to TGen dot ort slash news. The Translational Genomics Research Institute, part of city of Hope, is an Arizona based nonprofit biomedical research institution dedicated to conducting groundbreaking research with life changing results. You can find more of these podcasts at TGen dot org slash TGen Talks, Apple and Spotify and most podcast platforms. For TGen Talks, I'm Karie Dozer.

More TGen Talks
On this month’s TGen Talks, David Engelthaler, Ph.D., professor and director of TGen’s Pathogen and Microbiome Division, discusses the recent surge of bird flu, also known as H5N1.

H5N1 has been in the news a lot lately, but what does it all mean? Engelthaler breaks down the science and talks about the effects this particular strain might have on humans. He also explains what constitutes an outbreak, how they fade over time, and why they start anew.

Bird flu, like other influenza viruses, changes and mutates over time, and the H5N1 strain is particularly concerning. Although it is currently a low risk for human outbreak (there are only 3 known cases in the U.S. thus far), its impact on other animals, especially poultry and cattle, caught the attention of the CDC, USDA and other groups that monitor such outbreaks.

Engelthaler notes that outbreaks are often first noticed by wildlife managers or at zoos, where bird die-offs prompt testing for influenza. Over the past two years, the current bird flu strain has spread significantly by wild birds across North America and the rest of the world.

The good news: In Arizona, only one mammal, an Abert’s tree squirrel, has tested positive for H5N1 to date. TGen researchers are working with local wildlife and health officials to monitor the situation.
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