DENVER, CO. – A case of classical scrapie in a sheep slaughtered in a facility in Oregon has been confirmed. The National Veterinary Services Laboratories (NVSL) will conduct tissue‑matching and parentage testing on the affected sheep and two additional animals accompanying the affected sheep.
Animal and Plant Health Inspection Service (APHIS) and state animal health officials recently initiated an investigation to determine the flock of origin. Classical scrapie is highly contagious and spreads horizontally and vertically between animals. It is a neurodegenerative and chronic disease that affects small ruminants with a fatal outcome.
The affected animal did not have an ear tag, which may limit traceability.
Scrapie is typically contracted during pregnancy and newborn lamb periods, which is why locating the flock of origin is so essential to the investigation. This case highlights the critical importance of strong animal identification practices nationwide.
“The importance of official scrapie tags cannot be understated,” said Cindy Wolf, DVM and American Sheep Industry Association’s (ASI) Animal Health Council co-chair. “These tags have made trace back to the flock of origin possible in order to stop further spread,” added Roselle Busch, DVM and ASI Animal Health Council co-chair.
The investigation stems from a component of the National Scrapie Eradication Program called Regulatory Slaughter Surveillance, where brains from adult sheep and goat are examined by USDA. The positive animal was QQ (at codon 171) for scrapie resistance (susceptible genotype).
Prior to this confirmation, the United States had gone more than five years without a case. The United States was positioned to meet the World Organization for Animal Health’s (WOAH) seven‑year benchmark for self‑declared scrapie freedom in January 2028. Unfortunately, this confirmed detection could reset the timeline.
APHIS expects minimal impact on international trade. Most countries restrict live animal exports only from affected flocks or premises, and products such as wool remain unaffected.
USDA provides tools and reinforces key practices to help producers protect their flocks and advance scrapie eradication efforts nationwide:
*Ensure sheep purchased outside of slaughter channels have flock of origin scrapie tags. This would include breeding ewes, rams, and other life stages for grazing.
*Use of genetically resistant breeding stock, significantly reducing disease susceptibility. More info here.
*Robust surveillance participation, including submission of clinical suspects and routine monitoring.
*Continued partnership with APHIS and state animal health officials to support investigation and long‑term freedom efforts.
ASI will continue working with APHIS and the Oregon Department of Agriculture to support the investigation. Finding this case demonstrates the strength and ability of this program to detect such rare disease and highlights the exceptional progress made possible by producer participation. Additional information about scrapie and APHIS’ eradication program is available at www.aphis.usda.gov.
