BROOKINGS, S.D. -- South Dakota State University's Animal Disease Research and Diagnostic Laboratory is taking a leading role in combating a new strain of avian metapneumovirus, a virus that is causing significant economic loss to the United States poultry industry.
Avian metapneumovirus, or aMPV, is an upper respiratory tract viral infection that affects all types of poultry but is most harmful to turkeys. The virus is divided into four different subgroups: A, B, C or D. While each subgroup can be found in different parts of the world, the U.S. has previously only experienced outbreaks of subgroup C.
In January 2024, SDSU researchers became the first in the U.S. to identify the first known case of aMPV subgroup B after testing a sample from an outbreak in a North Carolina turkey flock. Since then, the virus has continued to spread throughout the United States, wreaking havoc for poultry breeders across the country.
"A and B, were worldwide in Europe, South America and Asia, but never detected in the U.S.," said Sunil Mor, assistant professor in the Department of Veterinary and Biomedical Sciences at South Dakota State University and section lead for virology at SDSU's Animal Disease Research and Diagnostic Laboratory. "First time introduction of the subgroups A and B in the U.S., it's a huge economic impact, especially on the turkey industry. The breeders are seeing up to 80% to 90% reduction in egg production."
In Minnesota, which is home to a major portion of U.S. turkey production, the virus has made a significant impact. Ashley Kohls, executive director of the Minnesota Turkey Growers Association, said the Association started conducting surveillance on the virus last spring. From April to June, they found that nearly 100% of the turkey flocks in the state of Minnesota were impacted by aMPV.
"It's unfortunate, and it's massive," Kohls said. "In addition to commercial turkeys or the meat birds, our breeder flocks are negatively impacted as well. For breeder birds, they have a significant reduction in the amount of eggs that they lay. Anytime you have breeder flocks impacted, there's ripple effects, obviously, through the entire industry -- less eggs, less poults, less birds, less turkey. It's kind of been a rolling compound effect. There's less baby poults, but then there's also less birds coming out on the back end because of sick flocks."
While the virus continues to cause issues for poultry producers, researchers at SDSU's Animal Disease Research and Diagnostic Laboratory are working around the clock. Their quick identification of the virus was a game-changer.
"I remember the first meeting Dr. Mor confirmed that it was subtype B, people were actually not even able to believe that," said Tamer Sharafeldin, an assistant professor Department of Veterinary and Biomedical Sciences at South Dakota State University and veterinary pathologist at SDSU's Animal Disease Research and Diagnostic Laboratory. "But, within a week, the USDA confirmed that as well, and that was actually a leading discovery for South Dakota State University."
With the virus confirmed, SDSU researchers pivoted to focus on vaccine development. They are currently working on three types of vaccines: a killed vaccine, a live attenuated vaccine, and a vector vaccine. The killed vaccine is the quickest to develop, as researchers can isolate the virus, inactivate it, and then test its safety and efficacy.
"We have isolated the virus, so we just inactivate it, test the safety potency, and then get the USDA approval to give it to the birds," Mor explained.
The team is also working to improve diagnostic tools, however, vaccine development remains the highest priority.
"The process is not going to happen in a day or two. It's going to take some time. We are actually competing with time to be able to achieve this," Sharafeldin said. "We have produced the weakened virus -- that's number one. Number two, we are starting to establish the baseline needed for vaccine safety and efficacy."
SDSU's leadership in identifying the virus and developing solutions is vital not only for South Dakota but for the entire U.S. poultry industry.
"There's a rapid need to develop vaccines for both the breeder flocks but also commercial turkey flocks as well. Developing that vaccine domestically will take some time, but there are a lot of folks working around the clock to make that happen," Kohls said.
"South Dakota State University is not only the university that serves South Dakota citizens, it's a university that leads research that would help the whole U.S. poultry industry in different states as well as it plays a very important role to enhance the U.S. economy," Sharafeldin added.