Georgie Cartanza, the University of Delaware Cooperative Extension poultry extension agent, stands in front of her four empty poultry houses in Mid March. She looks forward to a new, healthier, disease-free season ahead and a renewed sense of optimism from the lessons she learned over the winter of 2025.

Bird flu battle stations

Article by Michele Walfred Photos by Michele Walfred and Katie Peikes and courtesy of Georgie Cartanza March 18, 2025

UD on the frontline of avian influenza

In late fall, approximately 237,000 wild birds, representing 32 waterfowl species, fly south along the Atlantic Flyway from their Arctic home and settle along the Delmarva Peninsula. The impressive figure, calculated by the University of Delaware from surveys conducted by the Delaware Department of Natural Resources, includes the familiar snow geese, Canadian geese and ducks. In all, our temporary avian visitors rest and co-mingle in our local region before returning north at the beginning of spring.

For Georgie Cartanza, the flying V formations migrating overhead are cause for concern. As the University of Delaware Cooperative Extension poultry extension agent, Cartanza knows the odds are high that the wild birds are carrying avian influenza, which, if spread, is a direct threat to millions of broiler chickens raised on the peninsula — a $5 billion industry.

Highly pathogenic avian influenza (HPAI), or bird flu, is an extremely contagious airborne respiratory virus that spreads quickly among birds through nasal and eye secretions and manure droppings. It’s fatal to commercial poultry.

Cartanza is part of that community, raising organic chickens in four poultry houses. On her family farm in Kent County, she produces 148,000 chickens, totaling 5 million pounds each year.

Cartanza holds a baby chick in the summer of 2023 inside one of her four poultry houses located at her farm in Kent County. Cartanza raises poultry under strict organic guidelines.

During winter, Cartanza is constantly reinforcing her all-hands-on-deck approach to biosecurity in person and through her web page.

“One wild bird dropping contains enough virus to infect 1 million birds,” Cartanza warned growers in a fact sheet. “We cannot control where wild birds defecate, but we can take steps to prevent this virus from entering the houses.”

Wild birds were considered asymptomatic carriers until this season when they started dropping from the sky or failed to take off with their flocks. The University of Delaware Allen Lab in Newark tested the ailing and dead geese.

On Dec. 27, the first presumptive positive result of H5N1 avian influenza in sick and dead snow geese were reported in Delaware. The Delaware Department of Agriculture announced the results on Dec. 31 and alerted poultry growers to take precautions.

The announcement was a harbinger of more serious times ahead. On Jan. 3, a test from a poultry farm in Kent County produced a positive result, and a second farm soon followed. As a result, Cartanza reluctantly called for canceling three educational poultry sessions, an opportunity to reach hundreds of family farmers scheduled for January’s annual Delaware Agriculture Week.

The cancellation attracted media attention. Cartanza broadcasted her biosecurity message over the airwaves. Positive tests were increasing.

Cartanza’s instincts were spot on. From January to February, nine commercial poultry farms in Delmarva tested positive for avian influenza. Cartanza’s farm was one of them.

Ground zero for testing

In the poultry industry, when bird flu is not present, a scientific sample of commercial birds is selected from each flock and swabbed on a farm by a representative of one of five poultry companies, known as integrators.

“The samples are submitted in one tube and taken to our lab for testing,” said Kim Isaacs, manager of UD’s Lasher Laboratory located in Georgetown. “Birds cannot leave the farm for processing without the all-clear this test provides.”

Liliia Natareno, certified NAHLN technician at Lasher Lab, transfers RNA/DNA to a testing plate.

The primary test is a PCR (polymerase chain reaction), which accurately detects the presence of viruses through DNA and RNA sequencing.

Due to its central location within the Delmarva poultry region, Lasher is the primary lab used for flock testing. The facility is a Level 2 NAHLN laboratory. Both UD Allen and Lasher labs are two of 64 National Animal Health Laboratory Networks (NAHLN) operating in the United States, able to perform diagnostic testing for foreign and emerging animal diseases. Lasher is staffed by six NAHLN-certified technicians and one poultry diagnostician. The lab also performs serology and bacteriology testing.

“We routinely test farms all across the Delmarva Peninsula, including Delaware to Virginia, with other testing submissions from around the country, including the Carolinas, Ohio, Pennsylvania, and Georgia,” Isaacs said.

During the high-risk season, poultry farmers are alert to increased mortality. The normal threshold is three birds per 1,000.

“As a grower, you are supposed to contact your integrator’s service person that your mortality has gone up,” Cartanza said. “That will be the first indicator.”

Sylvie Smith, a NAHLN-certified lab technician at Lasher, places a sample plate into an automated RNA/DNA Extraction Instrument.

Cartanza said another warning sign is a decrease in water consumption, which should increase as birds grow.

When bird flu is confirmed, everything escalates to battle stations.

Lasher shifts to round-the-clock schedules. Personal plans are put aside and family obligations are sacrificed. There is no such thing as a snow day. Each of Lasher’s technicians knows that if one person goes out, it is a hardship for their coworkers.

Isaacs is proud of her small but mighty staff’s dedication and teamwork.

“The significance of the testing requires the technicians to work without a normal schedule, never knowing if they will leave on time or if they will be needed for weekend testing,” she said. “They put the needs of the industry ahead of their own during high volume testing periods, quickly providing testing results to the poultry industry so that they can make timely decisions.”

To compare, from January through February 2024, during routine, non-HPAI conditions, Lasher ran 1,200 PCR tests for avian influenza. This year, approximately 3,600 samples were tested at the same time frame, 2,448 of which were for the incident.

Aubrie Munsey, NAHLN-certified lab technician at Lasher Lab, prepares RNA/DNA avian samples for extraction.

On the frontline: Road to recovery

A positive result on a poultry farm is traumatic. And in late January, after nearly 20 years of operating her farm, Cartanza learned her farm was number eight.

Toward the end of January 2025 during the daily walkthroughs of her four houses, Cartanza observed increased mortality in one. She swabbed the birds and, through her integrator, submitted the tests. Within hours, Lasher Laboratory returned a presumptive positive.

Cartanza’s 148,000 birds were immediately depopulated, an unfortunate but necessary measure to control the virus like the seven farms before her and the one that would follow.

Cartanza knew the painful road ahead. A series of exacting procedures followed. After the depopulation, two rounds of composting, each lasting 14 days, are required, with temperatures monitored daily.

Once disease-free, the compost can be field applied. The farmer must remove all remaining organic matter from the houses. Next, the farmer sanitizes the houses, and environmental sampling occurs. Officials from the United States Department of Agriculture (USDA) debrief the farmer. The farmer is responsible for ensuring the farm is clean and properly disinfected. A two-week fallow period is imposed before the cleared farm can prepare for a new flock.

During “peacetime,” Cartanza welcomes students from the College of Agriculture and Natural Resource, shown here in 2018 for tours and a hands-on experience of how an organic poultry farm operates. This is one of many ways she uses her role as an Extension agent.

While Cartanza will eventually receive financial indemnity from the USDA for her flock, other costs and delays will cause her economic hardship.

Her immediate and profound sense of failure was far more upsetting to Cartanza than the loss of her flock.

“I felt I had let fellow chicken farmers down,” she said. “Despite communicating best practices, I still ended up with it on my farm.”

After reviewing biosecurity practices, Cartanza attributes an area of vulnerability to a combination of a large pond running parallel to her farm, which the property owner recently enlarged. That body of water created an oasis for migratory birds. An opening in a vegetative windbreak increased the risk of bird flu exposure on her farm.

Cartanza is exploring a laser light system to deter birds from landing in this area.

She vowed to rise above the negative and find a purpose for the pain.

Aerial observations will become part of Cartanza’s review process. She will share these updates with the poultry community so they can benefit, too.

“This real-world experience is humbling, but it’s helped me to be a better extension agent,” Cartanza reflected. “Someone told me afterward it was the best professional development I will ever get. It was a tough lesson, but now I can say with authority, ‘If it can happen to me, it can happen to you.’ That message will resonate with my fellow growers.”