On any given day, hundreds of samples arrive at the University of Minnesota Veterinary Diagnostic Laboratory for processing and testing. These days, many of those samples are vital to combating the ongoing highly pathogenic avian influenza (HPAI) outbreak as it continues to ravage the U.S. poultry industry and spread to other animal species—including humans. 

The Veterinary Diagnostic Laboratory (VDL) is on the frontlines of disease surveillance and testing and has processed and tested more than 115,000 samples for HPAI since July 2023. This includes testing samples from poultry, bovine, companion animal, and wildlife sources.

“We are making sure we are the eyes and ears for the disease,” said Hemant K. Naikare, director of the VDL, veterinary microbiologist, and professor in the Department of Veterinary Population Medicine. “We’re providing early disease detection in an accurate and timely manner, so when our results go out, response teams can act on them very quickly.”

The samples from poultry farms, dairy farms, and wildlife experts arrive at the lab’s Molecular Diagnostic, Serology, and Necropsy sections and are processed and tested for HPAI. This outbreak, which features a variant known as H5N1, is the latest in a long series of diseases the laboratory has been tapped to help mitigate through testing, surveillance, and research. 

Since its founding in 1904, the VDL has grown from a staff of four to around 110 people—and still needs more employees—to match the increasing need for testing and surveillance as new diseases and variants of existing ones emerge. 

The lab offers nearly 400 tests and services and is Minnesota’s only full-service laboratory for animal health diagnosis with its main facility in in St Paul and its satellite poultry testing laboratory in Willmar. It also serves as the official laboratory of the Minnesota Board of Animal Health and supports the national animal and human health system. The VDL is part of the National Animal Health Laboratory Network of 64 animal health laboratories helping state and federal government agencies respond to disease outbreaks. 

“We’re fortunate in that we’ve had decades of investment in high-throughput testing,” says Stephanie Rossow, a veterinary pathologist specializing in swine disease diagnosis and faculty advisor to the facility's polymerase chain reaction (PCR) laboratory. “We’ve been here and ready. We’ve encountered a lot of different scenarios over the years, so we’ve got a really good group of people that can accommodate the current need and get that testing done.”

Decades of expertise

In her 33 years with the VDL, Rossow has seen numerous disease outbreaks, including previous waves of HPAI. 

“Our first big event with HPAI was in 2015, and the state of Minnesota was really fortunate in that we had a PCR lab with a very competent staff available to conduct testing,” she says. “Without that resource at that time, the outcome of that event would have been very, very different.”

During the 2015 outbreak, the USDA estimates around 50 million chickens and turkeys were culled, with Minnesota flock losses accounting for 8.9 million of those deaths. As the top turkey-producing state in the U.S., containing the disease was vital to preserving the state’s economy. 

The most current HPAI wave involves a new variant of the virus first detected in U.S. commercial and backyard poultry in February 2022, resulting in the death or culling of more than 166 million birds. In the time since, this variant has been identified in wild birds and an increasing number of mammalian species, including seals, foxes, skunks, cats, and cattle. 

The disease also has zoonotic potential, meaning it can be transferred from animals to people. To date, there have been 68 confirmed human cases of HPAI infection since 2024, including one death in Louisiana. 

“Part of the concern with viruses like influenza viruses is they mutate, they change, they adapt to new hosts, and so the more time you give a virus to hang around and do that, the greater the likelihood that you're going to have a mutation,” Rossow says. 

Research impact

As alarm about HPAI continues to heighten in the U.S. in terms of public health, biosecurity, and rising food prices, research is key to gaining a better understanding of the virus.

The VDL plays an important role in those efforts, both on a state and national level. It will conduct surveillance testing for a recently announced $1.5 million cooperative agreement grant awarded by the USDA to researchers at the University of Minnesota College of Veterinary Medicine (CVM). The grant will support nine different projects aimed at understanding disease transmission and mitigating the impacts of HPAI on dairy herds and the broader agricultural industry.

VDL researchers also received a nearly $1.3 million grant from the Legislative-Citizen Commission on Minnesota Resources to launch an HPAI surveillance initiative that will assess its emerging threat to Minnesota wildlife with the help of collaborators across the state.

The lab also has been partnering with researchers at the University of California–Davis to study the virus’ impact on cattle, including how long the virus remains in the host and how long it takes a host to make antibodies.

Whether there is an active disease outbreak, Naikare says conducting research is a key part of the lab’s operations that allows it to respond effectively and efficiently to disease threats as they emerge. 

“We are contributing to applied research because a diagnostic lab is like a gold mine for samples. Veterinary medicine is a very interesting profession because you are dealing with more than one species,” Naikare says. “What a good sample is for one species may not be the optimal sample for another species for the same disease. So that's what we try to decipher. When we don't have an ongoing disease outbreak, we focus on applied research and developing new tools and diagnostic platforms so we get more accurate results in a shorter amount of time.”