TGen Talks: Episode 65
Karie Dozer [00:00:03] I'm Karie Dozer and this is TGen Talks. Most of us have probably already had Covid. But what does it mean when your dog gets sick with the virus that causes Covid 19? More than three years after the pandemic changed the way most of us were living our lives, we still get sick with Covid, and so do our pets. So while your dog might not feel or act very sick when infected researchers at Teach in North still want to study the virus in dogs to find out how it might be changing over time. And they're working with their partners and the One Health Collaborative to better understand the connections between humans, animals and the environment so that when a new mutation of this virus or another zoonotic illness appears, public health officials will be ready. And this episode of TGen Talks brings us to TGen North. Our guest for today's podcast is Haley Yaglom. Thanks for being with me today. And I'm talking about Canines and Covid.
Hayley Yaglom [00:00:58] Thank you so much for having me, Karie. I'm really excited to be part of our podcast.
Karie Dozer [00:01:02] Tell me what it is you do here at TGen.
Hayley Yaglom [00:01:04] I teach in North. I am the one health genomics epidemiologist, and basically that means I get to study infectious diseases across the human animal interface. So I bring a unique perspective to our infectious disease research at T Gen by looking at how pathogens spread between animals and people in that shared environment.
Karie Dozer [00:01:24] Tell me about what you're currently studying.
Hayley Yaglom [00:01:26] So we are doing a lot of work related to SARS-CoV-2, the virus that causes Covid 19. We've been doing that work at TGen North for the past three and a half years. And again, I really take a unique perspective by looking at that virus in animals to understand what that also then means for their human counterparts.
Karie Dozer [00:01:45] Are we more concerned with what Covid means to the dogs and to the cats, or are we concerned about what it means to have a dog or cat with Covid or be a human with Covid.
Hayley Yaglom [00:01:55] The interesting thing about Covid 19 is that it can cause a similar type of disease, although not as severe in animals as it does in people. But it's really important to consider studying diseases like this in animals, because SARS-CoV-2 is not the only infectious disease that can cause disease in animals and spread between animals and their human counterparts.
Karie Dozer [00:02:16] What does Covid look like in a dog or cat?
Hayley Yaglom [00:02:18] Yeah, so a lot of animals, including dogs and cats that do become infected with Covid 19 actually are asymptomatic. And we know that asymptomatic infections occur in people as well for those animals that do develop more severe infection, although, again, they don't typically develop infection as severe as people. It can look like vomiting, a cough, runny nose. And it again, is really important to look at that in animals, to understand the dynamics about how that could be spreading. We also have a lot of evidence that animals are not really spreading the virus to people that we know that the Covid 19 virus has been a human-to-human spread disease for the again, the entirety of the pandemic. And that's something that we really need to continue to be thinking about. Humans have been in the driver's seat when it comes to SARS-CoV-2 transmission this entire time. But as we see the virus continue to change, mutates, these new variants come about. We not only see transmission or spread from people into animals and then spread between animals, but there could also be the potential for animals to step into that driver's seat and start playing a larger role in spreading that virus back to people or to new types of animal species. And what that means for that shared environment.
Karie Dozer [00:03:46] Pet parents need to be more concerned about giving Covid to their dogs or cats than the other way around. That's what I'm hearing you say.
Hayley Yaglom [00:03:52] There's not that much evidence out there about transmission of this virus from animals back to people. There are a few very rare scenarios of animals spreading the virus to people. But again, primarily it is being spread to these animals, not just dogs and cats, but animals in zoo settings like bears and lions and monkeys, non-human primates. And it's coming from that close contact that people are having with those animals. Same concept as human-to-human spread. It's through that close contact. And one really important thing to highlight, because you mentioned pet parents is this immense connection that we have, especially with our companion animals. I have four dogs and two cats. My first few do, of course, and they're there. You know, my babies, they're my family. My dogs sleep with me. When I had Covid in 2021, I did my very best, especially as a researcher, to keep my distance and wear masks. But I needed to be responsible for caring for my pets. And we know that animals, again, are in close contact with people, especially in household settings, but also in other settings. So thinking about what that can look like and the types of connections and interactions that we have with our pets on a regular basis, sometimes the sharing of microbes is going to be inevitable. And in relation to SARS-CoV-2, that's exactly the dynamic that we're studying.
Karie Dozer [00:05:18] When we were going through the pandemic and there was at first very little information about the virus and where it came from, most people's concern was how did humans get this virus and why did it change in a way that affected us? Most of the evidence now points to truly an animal origin. So is it difficult for you to communicate the difference between that transmission, an animal to a human and a secondary transmission, which would be from a human to our pets?
Hayley Yaglom [00:05:46] Yeah. So I like to look at infectious disease spillover or zoonotic disease spillover, kind of like a domino effect. Zoonotic diseases are those that spread between humans and animals. Most of the time it goes from an animal into a person. We have so many examples of those diseases, especially in Arizona and the American Southwest. Rabies, plague, hantavirus. Others that maybe folks are familiar with. And SARS-CoV-2 falls into that category as well. And so, as you mentioned, we have so much evidence that shows that this virus, however it truly got into the human population, definitely has an animal origin, which is likely bats. And so there are viruses and other pathogens, other microbes that are circulating in animal species all the time. But they don't always spill over or get spread into other animal populations or other human populations. There's all of these things that need to be lined up perfectly for that spillover. And then establishment in a population again, whether it's a human population or an animal population or both, that needs to happen. So these other microbes and pathogens that circulate in bats or in wildlife populations, that's kind of the norm. With SARS-CoV-2, we have this very unique situation where it did then spill over into human populations. But then we've had these other scenarios and the dominoes have continued to line up perfectly that the virus has mutated or changed in just the perfect way that it's spike proteins, those little things that are sticking out in the pictures of the virus that make it.
Karie Dozer [00:07:29] Look so.
Hayley Yaglom [00:07:29] Scary, that make it look so scary, cannot just attach to human cells, but can also attach to animal cells and then continue to change in animals. So it just highlights this this bigger concept of why we need to continue to study this from all of these different perspectives. And how are those dominoes going to continue, potentially continue lining up to where we could see this establishment of these microbes in these other populations?
Karie Dozer [00:08:01] How many dogs and cats and humans will you look at? What are you studying and what are your methods?
Hayley Yaglom [00:08:06] We're really excited to be launching this study. We call it the 1000 canine SARS-CoV-2 surveillance study. And so in the title, we're hoping to get a thousand dogs over a two-year time period. And the unique piece about this study is that we're really looking to understand the dynamics of the virus and how dogs are getting exposed in different dog populations, so dogs that live and work in different settings. And this work actually expands upon a lot of pilot work that we did at TGen North in the earlier part of the pandemic. Looking at SARS-CoV-2 and its impacts on companion dogs and companion cats that are living in people's households. So in that original study, we found that of the dogs that we sampled, dogs and cats that we sampled across Arizona households, about 35% of those pets that we knew had exposure to their Covid 19 positive owners or another family member also were infected with the virus. It doesn't always mean that they develop signs and symptoms, but we know that about 35% did actually get exposed to the virus through close contact with their owners. There have been very few studies otherwise that have really expanded upon that initial concept and looked at dogs that are specifically dogs that are living and working in different settings.
Karie Dozer [00:09:24] What do you mean dogs working and living in different settings? Most people probably just think about a dog as their pet.
Hayley Yaglom [00:09:30] So there's actually seven different populations that we're going to be including in this project. The first is your typical companion dog. But we're looking at these other different populations, including dogs that are in animal shelters or humane societies that are exposed to a lot of different scenarios.
Karie Dozer [00:09:46] And a lot of different dogs and.
Hayley Yaglom [00:09:48] A lot of different dogs and people. We're looking at dogs that participate in kind of farm and ranching activities, thinking about how maybe those populations might interact with livestock. We're looking at free ranging dogs across our tribal communities as well as working dogs that police patrol, search and rescue dogs, drug detection dogs. Again, dogs that are really involved in a number of different activities and are interacting with people in other animals in a wide range of settings. We're also looking at companion dogs that are cared for by individuals experiencing homelessness. So another layer than your traditional household dog. And then we're also looking at therapy dogs. So these are these are companion dogs, but they're dogs that are going into hospitals or libraries or schools and providing some type of emotional support to the people that they interact with. And again, the broader concept there is really thinking about the. Environments and the difference in the environments that these dogs are interacting in and with. So not just you own a dog, and you live with them and sleep with them and feed them and do your routine activities. But what else could dogs be doing and how else could they be exposed to SARS-CoV-2 or other things? Interacting with people, interacting with other animals, including companion, livestock and wildlife. But also again in that shared environment.
Karie Dozer [00:11:14] Is the Covid virus that my companion dog has looked the same as the Covid virus. I might have.
Hayley Yaglom [00:11:22] It could, but it could also look different. And that's part of what we're looking to study. So one of the things that we do at T John North is a lot of genomic sequencing. So looking at the DNA and the RNA, you know, this genetic alphabet of the pathogen that we're looking at are of the microbes. We've been doing that a lot with SARS-CoV-2 over the past three years, particularly looking at the variants that are impacting people at a population level. So how those are circulating in our communities, we want to apply those same genomic technologies at the one health level to projects like this and will be we previously in our original work were able to sequence the virus, the Covid 19 virus out of a human sample pet owner and their dog and their cat. And we found that the virus was 100% identical at that time between the pet owner and those two pets in the household, likely showing transmission from the owner to one pet or both pets. And it was the first time that that was actually done. We were able to do that at T Gen because we also were sequencing Covid 19 positive samples from people. And so we want to continue to apply that for projects like this and we haven't yet. But if we find a virus positive animal, we want to sequence that sample and look to see what that variant is. Does it match what's currently circulating in the human population or is it different and how is it different.
Karie Dozer [00:12:54] And how might that sample compare to a sample taken three years ago? Because it's now 2023 and you've got some samples that are much older?
Hayley Yaglom [00:13:02] Yeah, those are all the things that we're going to be looking at. We do know that the virus that's circulating now, the variant of the virus, is much different in the human population as it was three years ago, because the virus itself has just continued to mutate and adapt. So looking and seeing where is it different? What aspects of the virus are mutating? And maybe a piece of that is also looking at how do we develop vaccinations in animals and in what are the environments in which these animals are being exposed, where we need to really be thinking about that Right now, it's not recommended to continually test your dog and cat that maybe comes in with a sniffly nose. There are so many other things that dogs and cats are getting and there is not a vaccination that is recommended in the U.S. for dogs and cats, but there is in zoo settings because we know that those zoo animals are highly susceptible. Several species are highly susceptible to the virus. So those are the important reasons to look at it, to answer some of the questions that you're raising of what is the difference? Let's find it and then we can answer all these other questions about it.
Karie Dozer [00:14:06] How long will your study take? What's the scope and when will you be finished?
Hayley Yaglom [00:14:09] Our study is running for two years. We started June of this year. We've got about 18 months left. We have already collected 300 samples out of our 3000 goal. The populations are kind of split up, so we get somewhat of an equal number of samples across those dog populations and then we can really start diving into that data and looking at those driving factors of how these dogs and in what environments are these dogs being exposed.
Karie Dozer [00:14:35] To most of these different diseases that do affect animals and humans and work together, so to speak, or transmit to one to another? Do all of those diverse diseases have anything in common?
Hayley Yaglom [00:14:48] That's such an important thing for us to really start to consider and look at? I mean, one thing that's different is that they're not all viruses. So for example, in northern Arizona and in the southwest, we do have plague, which we know is spread in a number of different ways to people and animals. And one of the unique things about plague to highlight when we think about our interactions with our companion animals is dogs can be exposed to plague, for example, is a bacteria, so it's not a virus. And the primary method of transmission is through the bite of an infected flea. So, for example, if somebody's dog is going out in their yard sniffing in those prairie dog burrows, the dog gets bitten by fleas, the dog could get infected with plague and then bring those fleas or just the bacteria back into the home environment. And then the person could potentially be exposed, or a person could go out in their backyard. And happened to be bitten by a flea. And so the piece that I'm bringing to light there is that there's these different dynamics and drivers interactions, activities about how the animal and then potentially as a byproduct, the person is getting exposed. And that's what is similar about SARS-CoV-2, is that there we know that there are potentially different factors that are driving how the virus could be spread amongst those populations.
Karie Dozer [00:16:15] It sounds like of all the human and animal relationships; the human and the dog is the most interesting to study because it is so common because there are so many kinds of different working dogs. And because so many families can't imagine their life without one. It's the one that is fairly reliable and there's a lot of good numbers out there.
Hayley Yaglom [00:16:33] Absolutely. We do know that the human dog bond and the human animal bond beyond that is so critical. And I think the other piece to highlight is then what else is the dog doing in its day-to-day life? Because we do have such close interactions with our dogs and that human dog bond, and that human dog interaction is so strong. But thinking back to our study, is that dog also a working dog that is going into schools and doing security and interacting and even maybe a lower level with hundreds of people in their day-to-day life. We can't study everything in every possible level, but there's all of these other considerations. So going back to your point about that human dog bond 100%, that's a really interesting piece. We want to take it to the next level and think about, well, what else does this dog do? Who else comes into your household and maybe brings with them other things?
Karie Dozer [00:17:30] Sometimes it's the UPS man.
Hayley Yaglom [00:17:32] Exactly.
Karie Dozer [00:17:33] Is there anything I've missed in asking about your study or the scope or what you hope to answer.
Hayley Yaglom [00:17:37] For this study? You've captured it all. I just really want to thank you for having me and highlight that this is really just a foundation with our one health work, and we're trying to look at a lot of other endemic and emerging pathogens, viral pathogens, fungal pathogens and bacterial pathogens that are important across our globe, but most importantly, Arizona and the Southwest. And look at it through the angle of how can we apply one health genomics to answer some of these questions about how pathogens and microbes in general move across that interface?
Karie Dozer [00:18:11] I bet a lot of pet parents listening had never considered all of the aspects of their dog getting Covid. Haley, thanks for your time and good luck with the study. Can't wait to see the results.
Hayley Yaglom [00:18:20] Thank you so much for having me again, Karie.
Karie Dozer [00:18:23] For more on TGen’s research, go to TGen dot org slash news. The Translational Genomics Research Institute, part of city of Hope, is an Arizona based nonprofit medical 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.
