Overview

• Highly pathogenic avian influenza (HPAI), commonly known as bird flu, has been detected in Washtenaw County, Michigan. In early February 2025, approximately 100 dead birds, primarily Canada geese, were found in the county, with preliminary tests indicating HPAI as the cause. An additional 60-70 birds were found dead near the Livingston/Washtenaw County line in January. These findings are part of a larger outbreak affecting over 300 wild birds across five counties in Michigan’s Lower Peninsula. 

• HPAI is a highly contagious respiratory disease affecting birds and some mammals, spreading through fecal droppings or nasal discharge of infected birds. The DNR advises residents to avoid direct contact with wild birds and to report any sightings of sick or dead birds to the DNR through their “Eyes in the Field” online tool.  (Source: Michigan.gov)

• The CDC closely tracks bird flu because of its potential to mutate and spread to humans, posing a pandemic risk, while also impacting agriculture, wildlife, and global health security. Recent cases, including the first U.S. death, highlight the need for continued surveillance, as even small genetic changes could increase the risk of a future outbreak. The H5N1 bird flu poses a low health risk to humans. While most cases occur through direct animal contact, a recent study found antibodies in veterinarians, indicating potential exposure without illness. This suggests that while the virus can infect humans, it does not easily spread between people, keeping the public’s risk low.

• Cathy Theisen, a retired veterinarian from Washtenaw County and an avian influenza first responder, has responded to poultry farms where HPAI was suspected and confirmed, and commercial flocks were “depopulated” to halt more infections. She says the HPAI outbreak has become an “economic and ecological epidemic”, especially for farmers who have lost their animals. But, all of us are feeling the fallout. In January 2022, the national average price for a dozen large Grade A eggs was approximately $1.93, and by December 2024, the national average price per dozen eggs had risen to $4.15. It is expected to increase further this year.

• Backyard chickens and ducks can become infected. Cathy advises that birds be kept indoors. HPAI has also been found in cattle, and milk is being sampled in Michigan as part of viral surveillance. 

• While the risk of severe illness for pets, including cats and dogs, is low, she emphasizes that pets should avoid unpasteurized milk, uncooked animal foods, and any contact with dead birds. Since pets live with humans, the potential for genetic mutation and transmission to humans makes it important to minimize exposure.

• Birds that typically congregated at feeders like chickadees, Northern cardinals, etc. are not known to spread HPAI, but corvid species (crows, blue jays, etc.) and waterfowl do. Bird feeders should be disinfected with 10% bleach solution every two weeks to prevent a variety of illnesses, and if waterfowl frequent a feeder it should be removed for now. 

Transcription

David Fair: Bird flu is a growing problem, and it’s making its presence known in Washtenaw County. I’m David Fair, and welcome to this week’s edition of Issues of the Environment. Highly pathogenic avian influenza is not only impacting commercial poultry farms, but in wild birds as well. In fact, in early February, approximately 100 dead birds were found in Washtenaw County, with preliminary results indicating bird flu as the cause. Obviously, there are concerns as to where this is headed and the impacts it may have. Cathy Theisen is a retired veterinarian and an avian influenza first responder from Washtenaw County, and she joins us today to share her observations and perspective. Thank you so much for making time for us, Cathy! I appreciate it!

Cathy Theisen: Thank you, David! I’m happy to share any information I can.

David Fair: In just reading up on it, I have the sense this is going to get worse before it gets better. What is your data and your expertise tell you?

Cathy Theisen: Yeah. I think we have some pretty strong evidence that it’s going to get worse before it gets better. This particular cycle of avian influenza began in 2021, and that’s a normal thing in wild bird flocks that cycles through. But this is a highly pathogenic strain, which means that, especially in poultry, it’s particularly deadly. So, historically, avian influenza has been an environmental and an ecological disaster because poultry producers and now dairy cattle producers lose their products. Ecological disaster because wild birds, even threatened birds, can have entire colony collapses. But now, as avian influenza is spilling over into other mammals and other species, there’s begun to be concern that it’s going to mutate into a situation where it can be transferred human to human, which would represent a pandemic.

David Fair: You’re just full of good news, aren’t you?

Cathy Theisen: Yeah.

David Fair: I mentioned in February that some 100 wild birds were found dead in the county, most of them Canadian geese. Preliminary indications, the culprit: avian flu. Additionally, in January, 60 to 70 wild birds were found dead near the Livingston/Washtenaw County line. Regionally, over 300 cases of fatal bird flu among the wild flocks. Where are the wild birds picking up the disease?

Cathy Theisen: Well, again, it’s a normally cyclic disease. So, it’s always kind of out there in the wild population. They don’t socially distance. When one bird gets ill, it’s very easy for it to spread through the entire flock. And then, certain birds, like ducks, for instance, are thought to have a little bit of resistance. So, some of them become carriers, even though they themselves are not sick. Canada geese, swans and certainly ducks too will die from the disease, and then their body becomes a reservoir of the virus. So, animals that scavenge on them, or other birds that swim in the water near them, can then keep the cycle going.

David Fair: Our Issues of the Environment conversation with retired veterinarian and avian flu first responder Cathy Theisen continues on 89 one WEMU. Now, you mentioned how devastating it is for poultry farms. Pretty much the entire population either dies or has to be destroyed. Correct?

Cathy Theisen: Yeah, it doesn’t die. This has been going on in poultry for a long time. So, there are some very strict guidelines. For instance, when I have responded to an avian influenza outbreak, what happens is I approach an infected poultry farm, park at the very end of the driveway, there will be a garbage can. Any birds that died that day are taken from the garbage can, and tracheal swabs are taken. I would be dressed in a high-neck suit, rubber boots, a respirator, the whole nine. I would then decontaminate myself and also decontaminate my vehicles, so even the wheels of the car, the undercarriage of the car before I would go to another poultry facility for more testing. If the facility gets a positive bird, the entire bird house is depopulated. They are euthanized immediately because it is very highly pathogenic and can be transferred from house to house. But poultry owners know this and have been very careful about biosecurity for years. The bigger issue is that we just started seeing it in 2024 in dairy cattle. And historically, dairy cattle have not had a good biosecurity in place. The USDA has declared an emergency because of the dairy cattle, and now milk from dairy cattle farms is tested monthly. If there’s a positive, then there’s a whole algorithm of things that happen on a dairy farm, too. So, that’s kind of the new thing. That’s a bit scary. And workers on dairy farms have much closer contact with their animals. So, on a poultry farm, they’re living in a barn, they’re fed and monitored. But there isn’t day-to-day or hands-on contact in a dairy farm. The cattle are milked twice a day, so you could potentially have workers that get milk squirted in their eye, get manure on themselves, so there’s a much greater human-to-animal interface there. And so, it’s a concern about how we can develop biosecurity measures for dairy cattle.

David Fair: Like everything else that is going to require an evolution, with that in mind, how concerned are you that new attitudes and potential policies in the realm of public health may worsen the situation?

Cathy Theisen: Extremely! Specifically, President Trump has indicated he would like the United States to not have a partnership with the World Health Organization, which is the organization that oversees these sorts of diseases. So, if a disease like this pops up someplace in Africa or Asia, it certainly behooves the United States to send our best scientists over there, figure it out when it’s not in our country, get vaccines going before it’s in our country. But when we excise ourselves from the global scientific community, we lose the ability to keep those diseases from entering our country. So, yeah, I’m extremely concerned about any trimming of scientists that are working on epidemics or pandemic-type diseases.

David Fair: The price of eggs, the potential threat to milk–all of that has become a political issue beyond just a public health issue. How do we negotiate the politics?

Cathy Theisen: That’s a tough question. For me, the answer is easy. I’m a scientist. And so, I would go with the science. If we have a disease that is beginning to take hold in our country, we react quickly, and we get our best epidemiologists and scientists to work. The price of eggs is not a political problem. The price of eggs is caused by the number of birds that have had to be depopulated. So, there are many, many, many, many less laying hens in the United States because of this disease. Many poultry producers are begging for an avian influenza vaccine because, even though the government gives them some recompense for the birds they lose, it’s never the same as market value. They would much rather have a vaccine and be able to continue on. It is very hard for me to think of disease as a political situation.

David Fair: The vaccine has become one of the longer four-letter words in the American vocabulary.

Cathy Theisen: Yes, it has. And, again, I cannot understand that.

David Fair: So, our time together is running short. But I do want to ask a final question. So, based on what you know today, what you see out in the field and where we seem to be headed in terms of public policy, if we look out five years, are we in better shape or worse shape than we are today?

Cathy Theisen: Well, I’m an eternal optimist. So, I hope that clarity and reasonable thinking will return and that we will, even if we get a late start, America is a very accomplished country that can certainly coordinate with the world to try to stop the spread of these diseases. So, I hope that we will have awakened to the dangers that are out there. And, again, I don’t want your listeners to think that avian influenza is a major situation that is occurring in people. It is not. The risk to people right now is very, very low. But there are warning signs that that is changing. So, now is the time to act, not once it becomes a pandemic or an epidemic for people.

David Fair: Well, Cathy, thank you so much for your time today! And there will most certainly be occasion for us to talk again down the line.

Cathy Theisen: Thank you so much, David!

David Fair: That is Cathy Theisen. She is a retired veterinarian. For more information on highly pathogenic avian influenza or bird flu in our area, stop by our website at wemu.org. Issues of the Environment is produced in partnership with the office of the Washtenaw County Water Resources Commissioner. And you hear it every Wednesday. I’m David Fair, and this is your community NPR station, 89 one WEMU FM Ypsilanti. Celebrating 60 years of broadcasting from the campus of Eastern Michigan University!

Non-commercial, fact based reporting is made possible by your financial support.  Make your donation to WEMU today to keep your community NPR station thriving.

Like 89.1 WEMU on Facebook and follow us on X (Twitter)

Contact WEMU News at 734.487.3363 or email us at studio@wemu.org