Swine farms vary in their risk from endemic PED

Recent analysis indicates the counties with more swine farms are more likely to have outbreaks of porcine epidemic diarrhea.

An article published in January by National Hog Farmer notes that the PED virus has become endemic in the U.S. The overall number of cases has been declining since the virus emerged in U.S. swine herds in 2013, and the risk of outbreaks today varies by region of the country, season, and number of swine in the area, it states.

The authors, from the University of Minnesota Department of Veterinary Population Medicine, indicate the PED virus persists in the swine breeding herd with low incidence.

The researchers analyzed data on PED surveillance collected July 2014-June 2021 from 1,100 breeding farms in 27 states. The data came from the Morrison Swine Health Monitoring Project at the University of Minnesota, and the researchers identified 625 outbreaks at 373 farms during that time.

Kimberly VanderWaal, PhD, who is one of the article authors and an associate professor in the University of Minnesota Department of Veterinary Population Medicine, said the project tracks PED in about half the U.S. swine breeding population, and about 7% of those sow farms have a PED outbreak in a typical year. The regions with low incidence could move toward eliminating the virus with a concerted industry effort, she said.

Dr. VanderWaal said the research team also has found that, on average, a typical sow farm would have an outbreak about once every 10 years, down from once in 2.5 years early in the virus’s emergence in the U.S.

The Swine Health Information Center funded the research. Dr. Paul Sundberg, executive director of the SHIC, said the biosecurity measures to keep PED off farms are well known.

“We’re having reasonably good success at keeping PED at a relatively low level,” he said. “That being said, there are still instances where we are investigating outbreaks to help find the lapses in biosecurity that enable outbreaks.”