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Melanie Cole (Host): Avian influenza or bird flu has been in the news this past year due to a highly pathogenic strain that has caused illness and death in a variety of species around the nation. Welcome to UF Vet Med Voice with the University of Florida College of Veterinary Medicine. I'm Melanie Cole. And today, we have a panel to provide updates and share information relevant to owners of pet birds, as well as how the virus is a potential danger to other species, including humans.

Joining me is Dr. Jim Wellehan, he's an Associate Professor of Zoological Medicine and Microbiology at the University of Florida College of Veterinary Medicine; and Dr. Amy Alexander, she's a Clinical Associate Professor of Zoological Medicine at the University of Florida College of Veterinary Medicine. And they are both with the UF Small Animal Hospital Zoological Medicine Service, through which they see and treat birds of a variety of species.

Doctors, thank you so much for joining us today. And Dr. Wellehan, I'd like to start with you. Tell us a little bit about avian influenza or bird flu. What is it? How prevalent is it? Give us a little background.

Dr Jim Wellehan: Well, so the influenza of viruses are in group of viruses called the orthomyxoviruses. And there are some that are more isotropic for bird hosts. But one of the things that really stands out about influenza virus is is they're better at jumping around between different hosts.

A very important part about their biology is that they're broken up into different pieces. They have genes on different pieces of DNA, so they can kind of swap them around like we do with chromosomes. So a very similar virus is the measles virus that we all give vaccinated for as children, I would hope. And when you get vaccinated for measles virus, it's biologically very similar except it's one solid piece and it doesn't recombine very well. And so the measles virus you're vaccinated for against as a kid is still pretty much the same virus that's going around and you still have immunity. The big difference with flu is when two flu viruses infect the same cell and they love each other very much, they can swap around their chromosomes and you come out with a new flu virus that has some genes from one parent and some genes from another parent virus, and it's a whole new thing. And so the reason we get flu vaccines every year is because the flu virus is no longer the same virus that we got vaccinated for last year, and it's capable of much more rapid evolution.

And so, it'll reservoir in different hosts, but basically it changes so quickly that every time we see flu coming through, it's something new and different, and it kind of resets our expectations on how it's going to present clinically. It resets our expectations on what sort of hosts are most likely to be infected. And it resets our expectations on a lot of ecological parameters for it. And so this year coming through happens to be really bad in a lot of wild birds and is very pathogenic. And so we're seeing a lot of mortalities, and it's done some jumping into some mammals as well, which is a little concerning.

Melanie Cole (Host): Wow. That was such a comprehensive answer. You're a great educator, Dr. Wellehan. Thank you for that and for really giving us that overview. And Dr. Alexander, what are you seeing or not seeing in regard to bird diseases in general, including avian flu? Why is this particular disease of specific concern and the different variants that have shown up in the past? Tell us what you're seeing right now and around the country what you're seeing.

Dr Amy Alexander: Yeah. The past few months, we have been seeing the loss of especially wildlife populations of birds. So the species that have been most common in the wildlife populations are especially the black vultures, the duck species and also the bald eagles. So there's been die-offs in wildlife populations that the public luckily is recognizing, and they're calling wildlife rehabilitators and Florida Fish and Wildlife and reaching out and notifying them of what's happening, so those cases can be tracked. But it's been a big issue in those populations. And then, our concern, you know, we treat wildlife at the University of Florida in our clinic, but also see pet birds as well as pet poultry, so people's pet chickens and turkeys and ducks. And so there's the concern of could this also spread into people's pets as well.

Melanie Cole (Host): Wow. So Dr. Wellehan, what does this mean for bird enthusiasts with backyard feeders? I'm one of those. And bird baths, I have one of those. Tell us a little bit about what this means, why this recent strain is so dangerous. Are songbirds at risk? Tell us a little bit about what this means for us.

Dr Jim Wellehan: Well, so again, we're still trying to figure out a little bit about the host range. Amy mentioned that black vultures are having a huge problem with this. And it tends to be the species that's most commonly affected around here that we see. But turkey vultures, who are pretty close relatives, don't seem to be anywhere near as badly hit. And there is definitely an investigative bias towards things that are big enough to get found and seen and brought in for examination. And so songbirds is definitely an area of weakness, as far as our understanding of what the host range is. We know that in general, that when you do things that encourage animals to come face to face, that it's really great for pathogen transmission. And so when we have birds coming together at a bird feeder, there's going to be major concerns about that.

Melanie Cole (Host): Yikes. I guess that means that I should be doing different things. So Dr. Alexander, what are we supposed to do? And how do we protect backyard chickens, ducks? You know, tell us what we should be doing. Should I be taking down my feeders?

Dr Amy Alexander: It's an excellent question about what should you do when you have outdoor pet birds or you have bird feeders. And there are recommendations, if you can safely bring your pet birds inside, which if you have pet parrots that have an outdoor aviary, that's much easier. But if you have pet chickens or ducks that have to live out in a pond, what do you do? And so you really do try to limit interactions with wild birds. So if there would be treetops or things above your enclosure with your pet chickens, maybe try to trim back those branches so that maybe wild birds aren't above them and defecating or dropping material into that enclosure and trying to reduce any wild birds that might be on your property. If you have wild vultures that come in and feed, maybe trying to move your feeders so that they're not attracted to it.

And you asked about, you know, your wild bird feeders. We've had people who have taken down their feeders, so you don't cause them to congregate as Dr. Wellehan was saying. But then, some of my friends who have done so, all the wild birds then started going into their chicken enclosures and so then their pet chickens were actually at greater risk. So it's really a give or take and trying to reduce the risk as best you.

Melanie Cole (Host): Well, then, Dr. Wellehan, humans, other mammals, our dogs, our cats, we have other animals around and for people that do have feeders, bird baths, things like that, should we be worried about the droppings? Should we be keeping the area clean? What about ourselves and our pets?

Dr Jim Wellehan: Well, that's still a fairly open question at this point. We are seeing definitely there are a number of mammals that have been affected this year. Foxes were one of the ones that were recognized early in the process and skunks. But we've recently had a case that was treated by our aquatic animals medicine service here at the university. There was a bottlenose dolphin that just succumbed to primarily encephalitis or inflammation of the brain from avian influenza that was also in its brain.

One of the unusual things about this year's version of influenza, is it tends to be very neurotropic and we see a lot of neurologic signs associated with this, when most flu viruses we think about it primarily being respiratory. This is a very neurologic strain this year.

Melanie Cole (Host): Talk about those symptoms.

Dr Jim Wellehan: Birds are obtunded. They become mentally dull and kind of don't behave normally and have decreased normal mental function.

Melanie Cole (Host): What about things like skunks, Dr. Wellehan? You mentioned skunks and other wild animals, rodents, things that we might see around. Are there things we should be keeping an eye on? We hear about rabies and what you should look for, but what about this?

Dr Jim Wellehan: Well, rabies is another primarily neurologic infection, that can present in a lot of ways very similarly to this. And so, there's definitely some overlap as far as clinical presentation goes. And I would advise that going and grabbing a rabies-positive animal or an influenza-positive animal is probably not a great idea, and you may probably want to talk to some animal professionals about that.

Melanie Cole (Host): Well, that leads very well to the next question. Dr. Alexander, what should we do if we find an injured or a dead wild bird? I remember years ago when the crows were laying around on the sidewalk and what we were supposed to do. What do we do now?

Dr Amy Alexander: That's a good question. And ideally, do not touch it. If you need to move it because you could have your own pets exposed, you can grab it using double garbage bags if it's a deceased bird or wildlife and put it in two trash bags, but not actually have any contact with it, with your own hands, and then take a shower afterwards.

If the animal is alive and you have concerns, definitely reach out to any local animal professional, whether you can try contacting Florida Fish and Wildlife Commission. You can call your local animal control, your local veterinarian or a wildlife rehabilitator. And any of those groups will be able to get you to the people that can help and come check out the situation.

Melanie Cole (Host): Wow. This has been so informative. Dr. Wellehan, last word to you. What would you like the key takeaway to be for other providers, other vets, and for listeners that are concerned about this, but still love to watch the birds and feed them and all of that? What is the key takeaway for this year's avian bird flu?

Dr Jim Wellehan: Well, the key takeaway for the avian influenza this year is that it is pretty rough this year on our native birds. But if you're watching them through a set of binoculars, you're not going to pick up avian influenza from that. And so, it's close contact that we're going to be concerned about. And again, when it comes to jumping into other species, that is something we want to be aware of. And I think, especially practitioners, this is something they should have on their differential list.

When the dolphin presented here, everyone had kind of operated under the assumption that it was likely to be a morbillivirus, which is another virus that causes encephalitis in dolphins. And it came as a surprise to us all, that it was avian influenza. So just to be aware that some of these animals out there that have neurologic signs may be because of flu and some of the public health folks probably want to know about that.

Melanie Cole (Host): Thank you both for joining us. And I hope that you'll come back again and update us as you learn more. And as these things mutate and we learn more about new strains, please join us again anytime. For more information about the University of Florida College of Veterinary Medicine and to listen to more podcasts from our experts, please visit vetmed.ufl.edu/ufachievers.

That concludes today's episode of UF Vet Med Voice, brought to you by the University of Florida College of Veterinary Medicine, advancing animal, human and environmental health. I'm Melanie Cole. Thanks so much for listening today.