How PRRS Has Made the Summer of 2025 Frustrating and Unforgettable

Despite the layers and layers of biosecurity in place, porcine reproductive and respiratory syndrome (PRRS) keeps finding a way through. It’s very challenging for farms and veterinarians trying to fight this costly disease.

“A couple years ago, I felt like a good vet every summer. Then, every winter, I felt like a terrible vet because of PRRS and influenza,” Cara Haden, DVM, director of animal welfare at Pipestone, said during the Q2 State of the Pork Industry Report. “It seems like these challenges are not seasonal anymore. It has been a really, really frustrating summer for the industry.”

She says modern strains are different than what the industry has battled in the past. Recent research led by Christine Mainquist-Whigham at Pillen Family Farms and Daniel Linhares at Iowa State University’s College of Veterinary Medicine have described extended shedding periods and times where animals have started shedding again after previously negative tests.

“We’ve got a summer intern project right now where we’re looking at gilt shedding,” Haden says. “We’re really frustrated with the amount of time that some of these gilts are shedding after intentional exposure during a closure.”

Are We to Blame?
Adam Annegers, sow production manager at JBS, wonders if the industry is “doing it to ourselves.”

“Part of it is veterinarians have done their jobs too well, and we’ve eliminated all the little weak viruses out there,” Annegers says. “Viruses adapt and they survive. As we continue to eliminate the little softies out there, the viruses that remain become a lot tougher. You definitely feel the effects more when they come in now.”