How scientists and farmers work to adapt

Avian influenza virus continues to affect poultry producers and dairy products in 2025. In North Carolina alone, the virus has lost millions of birds on poultry farms. Meanwhile, less than a year after the first detection of avian influenza in dairy herds, a new strain of the virus was discovered in Nevada cows.

To understand the latest developments, I consulted Matt Koci, a virus expert and professor at NC State University. Priest Bureau of Poultry Sciencepeople who are paying attention to bird flu.

What is the latest developments in poultry avian flu?

A big change that has been true over the past few years is that avian flu remains here, and it is becoming a more present threat and danger to poultry. That risk increases at different times of the year, but does not return to zero as before. The outbreak of avian influenza may be linked to bird migrating patterns, but now the virus appears to be established in wild birds living in the United States, including North Carolina. Last week there was a report of a large horned owl that was found dead along with the bird flu in Wake County. There are big risks all year round. This is because they are among local birds, not just birds, but also birds passing during the migration season. This differs from what we saw in 2015, even in 2021 when the outbreak occurs, but after the bird's movement, the case disappears and things return to normal. Around 2022, avian flu cases fell but did not disappear in all states.

The poultry industry is adapting to evolving threats. But until recently, what we always told poultry producers, farmers and the public was that bird flu was introduced when migratory waterfowls, ducks, geese and other birds, were flying. And what people did to keep wild birds away from biosecurity and poultry focused on migratory waterfowl. With the bird flu becoming a local wild bird, there may be more birds that farmers need to be aware of. The way H5N1 enters poultry homes is likely changing, so farmers must adapt to it too.

So far in 2025, how has high pathogenic avian influenza or HPAI impacted the poultry industry?

On the laying side alone, more than 3.3 million birds have been lost in North Carolina since the beginning of 2025. In the last 30 days, the US has lost around 20 million birds. Over 18 million people lay chickens. To replace those spawning hens, it takes about 20 weeks for the hens to hatch and the hens to mature for egg production. However, you also need to note that it takes time to clean each farm after the outbreak. Therefore, each of these farms can become unproductive for at least 2-3 months. It takes time to replace 18 million birds, and while the bird flu is still around, we are still losing birds at the same time.

Has bird flu also evolved in dairy cows? There was recent news about the second strain found in Nevada dairy cows.

Currently, the H5N1 bird flu is still found in dairy cows in Nevada, but it follows another evolutionary path through wild birds. Both the detected new strains of H5N1 and the strains that have become dairy cows for some time are associated, but they evolved slightly differently. For a long time, there was really only one strain of bird flu that we had found in cattle, but all the cases seemed to be tied together. The idea was that there was one introduction to the cow in the southwest, and all other cases were relevant.

This new case suggests that the virus jumped a second time from the bird, so this case has nothing to do with other cases. This is because there are several distinct differences in the H5N1 strain of dairy cows genetically. They are still H5N1, but they are like the difference between Omicron and Delta in the Covid-19 virus. We know they are both SARS-COV-2, but they were different, and this is kind of the same situation.

What is the importance of finding new strains of H5N1 in dairy cows? Should I worry?

It is difficult to draw a big conclusion about what that means. There is no evidence that the virus has evolved in ways that have improved infecting mammals. It has mutations that we generally think will help in infect mammals, but there are only one of these, and one is not enough to really get better. It's not good news, but there's no reason to think it's worse news than what we already deal with. That probably means that what happened in Texas happened again with a different, closely related virus.

I don't know exactly how these Nevada cattle, which have a new strain of H5N1, were infected. It is not yet 100% clear how the original Texas cows were infected. The strains found in Nevada cattle are more suitable to what we found in wild birds scattered throughout North America.

From a prevention perspective, what are scientists doing to prepare in case this virus spreads more widely?

All labs already engaged in the research of avian flu work as hard as possible. For avian flu that is deadly for poultry, you need to have a certain type of lab with specific biosecurity so that you can tackle the avian flu and understand how it will change. Many labs in the US have not been built to provide the level of biosaving needed to perform these types of experiments. And unfortunately, that includes the NC state. There's a bottleneck there. Many poultry companies and dairy companies now have many questions, but there are not enough labs to do research to answer the questions.

We have been preparing for an avian flu outbreak for a while. Tabletop exercises were held. The government has put in many resources, including funding for the Holly Springs vaccine plant to be paid for in Barda [Biomedical Advanced Research and Development Authority] money. It started in the late 90s when it began to appear that avian flu could first jump to people. It scared many people and governments around the world, led by the US and the World Health Organization. [WHO] I started to place the pieces.

Over the past 20 years, there has ultimately been a lot of foundation for people regarding the development of avian influenza vaccines for birds. That includes many initial tests to figure out what kind of vaccines are effective, even for birds and humans. Currently there is no market for 300 million bird flu vaccines for humans, but if that day comes, you should be able to crank them out right away. If you need a vaccine, we hope there is more public trust than we saw when the Covid vaccine was rolled out. Hopefully we don't need to find it. Preparing is a good strategy to prepare for what avian flu ecology once looked like, as the ecology of avian flu changed here.

What else should people know about bird flu?

North Carolina is one of the most prepared because it is one of the most practiced things in addressing these types of threats and challenges. Much of this bird's flu preparation, at least on the poultry side, came from our hurricane disaster response team. When a hurricane collides, many farms to the east are flooded. Hurricane Floyd in terms of building infrastructure to reclaim and run farmers in response to natural disasters. [in 1999]perhaps a Pinnacle example. We have developed ways to protect citizens, protect property, and get farmers to run and operate. The state's emergency team brings veterinarians, so the North Carolina Department of Agriculture is a disaster response, and if not, farmers are coming in and helping farmers, the US Department of Agriculture will overdo the farms, test them and make sure they are virus free.

It's bad enough for farmers to lose all their birds and their livelihoods during an outbreak, but there's a few months of downtime afterwards. The state worked together as a partner with the USDA to find ways to hire as many farmers and workers as possible and generate income as quickly as possible. We know that the effects will ripple over the economy, but it's difficult to calculate all the methods. I know how much I spent to get the farmers back to work, but how much money was lost in local feed and seed shops, or in waffle houses down the street when people left their jobs? How much did taxpayers cost as egg prices rise twice, three times, and five times? The new reality of this endemic avian flu is no longer just affecting the outbreak, but also the impact.

How about using a vaccine?

Vaccines can be used. There have been reports that some vaccine companies have already received approval to start manufacturing vaccines for use in birds, but that doesn't mean that companies will use them. Vaccinating birds creates problems with international trade. There are many nuances, but the short version looks like this:

All countries that are part of the World Trade Organization [WTO] And wanting to sell poultry products in international markets is necessary to demonstrate that the list of diseases is not in the flock. If your bird can show that it is completely free of bird flu, other WTO trading partners are expected to accept your product. The WTO does not prohibit the use of vaccines, but other countries do not need to take the product when vaccinating. We have always sought to produce poultry without vaccination to eliminate doubt and avoid raising concerns about trade.

Historically, the US had to deal with sporadic avian flu outbreaks, allowing it to happen quickly with its strategy of not using vaccines. The cleanup costs for the outbreak were expensive, but in the long run it was cost-effective on a macro scale.

Now, ask for a question, can we maintain the old way of getting bird flu? Is that approach cost-effective overall? We don't know, but we need to do math. If you haven't crossed that line yet, you're probably really close. But the industry knows that once we cross that line we can't go back. We will likely be able to address the new virology challenges that come with that decision, but we don't know exactly what it means for the economics of poultry production. Poultry is a huge sum of money, especially for North Carolina. No one wants to make this decision until it turns out that it is the only option we have.