Data from its avian influenza tracking project is alerting poultry producers, the public, and wildlife rehabilitators to upticks in cases, where they are occurring, and precautions to take
A great horned owl's beak is held open as a Raptor Center staff member swabs the inside of its mouth to collect a saliva sample to test for highly pathogenic avian influenza.
From tiny owlets to mighty bald eagles, every bird admitted to The Raptor Center at the University of Minnesota these days is playing an important role in disease surveillance efforts.
The raptors are tested for highly pathogenic avian influenza (HPAI), and with each test result, center staff members are building a bank of knowledge they hope will safeguard lives and livelihoods.
As of mid-April, more than 5,000 birds brought to the center’s hospital have been tested for the disease since March 2022. While the results provide insight into the disease’s prevalence and spread, they also hold promise as an early warning system for poultry producers, wildlife rehabilitators, and the public.
“We looked at when we detected bird flu relative to when it first showed up in poultry last fall, and a bald eagle patient that was admitted to our hospital tested positive for the disease 10 days before the first poultry farm was affected,” says Dana Franzen-Klein, an avian veterinarian and the center’s medical director. “These test results in raptors could serve as effective early surveillance to alert poultry producers that the virus is present, and it's time to up their biosecurity.”
Highly pathogenic avian influenza spreads through bodily secretions such as saliva and feces, and can hitch a ride into poultry farms on contaminated footwear and vehicle tires. Farms have stringent biosecurity protocols to combat threats like this, but if the virus slips through, its impact is devastating.
The U.S. poultry industry has experienced historic losses since this particular strain of HPAI began circulating four years ago. The USDA estimates 200 million birds across 1,000 commercial flocks have died or been culled since 2022.
In Minnesota, more than 10 million birds have been lost from commercial flocks in that time frame, according to data maintained by the state’s Board of Animal Health. As the country’s No. 1 turkey-producing state, having an early warning system for the virus would save animal lives and protect the livelihood of nearly 20,000 people employed by the industry.
In the past, outbreaks of HPAI typically ended after a single spring or fall migration season. Since 2022, the current strain has continued to circulate over multiple years, impacting wild and domestic bird populations instead of fizzling out in a few months with the seasonal change.
“With avian influenza, like human influenza, there are lots of different strains of the virus—the highly pathogenic strains can make poultry very, very sick,” Franzen-Klein says. “Ducks and waterfowl often can carry these HPAI viruses and do not get sick. The HPAI strain that is currently circulating is behaving differently from outbreaks we've had in the past and is making those wild birds ill—it caused a huge die off in those species back when it emerged in 2022.”
Since this strain’s emergence, staff members at The Raptor Center have put robust biosecurity protocols into place and have gathered data to better understand the disease and its transmission.
That includes drawing blood from more than 2,000 birds to test for antibodies. The results of this work have revealed that more raptors than anticipated are surviving what is typically considered a fatal disease.
The Raptor Center’s work around HPAI has been supported by a two-year, $187,000 grant awarded in 2024 from Minnesota’s Environment & Natural Resources Trust Fund, and the impact of these response efforts reaches farther than the poultry industry. This year, the center was selected to receive a second grant for $298,000 to continue this work.
Every bird brought to the center—alive or deceased—is tested for HPAI. Most come from the Twin Cities metro area, but they do receive birds from around the state and western Wisconsin. Test result data is publicly available on the center’s website, including recovery locations of birds testing positive for the disease. Franzen-Klein says results are shared directly with people who find a distressed or deceased bird on their property.
“Testing every single bird gives us a broader picture about how the disease is behaving in the area where those birds come from and provides information for the community as a whole,” Franzen-Klein says.
The Raptor Center also developed and enacted heightened biosecurity protocols in response to the outbreak, including quarantining all admitted birds until they test negative. To date, there has not been a case of a bird or person contracting the virus from an HPAI-positive bird within the center.
These protocols have been shared widely within the wildlife rehabilitation community in Minnesota and beyond. Through publications, webinars, direct mentorship, and conversations, Franzen-Klein and The Raptor Center have ensured rehabilitators have access to practical evidence-based information to guide their work.
