US detection of classical scrapie in Oregon could delay country’s scrapie-free status

US authorities have confirmed a case of classical scrapie in a sheep in Oregon, marking the first detection in over five years and potentially impacting the nation’s bid for international scrapie-free recognition.

US authorities have confirmed a case of classical scrapie in a sheep slaughtered in Oregon, the first U.S. detection of the fatal disease in more than five years and a setback that could delay the country’s bid for international scrapie-free status.

The US Department of Agriculture’s Animal and Plant Health Inspection Service said the animal was picked up through routine slaughter surveillance. Regulators are now working with Oregon officials to trace the flock of origin and are conducting tissue and parentage checks on two other sheep that travelled with it.

According to APHIS, scrapie is a prion disease of sheep and goats that can take years to show clinical signs, making surveillance and animal identification central to control efforts. Oregon officials say the disease is incurable and is usually spread from ewe to offspring through contaminated birth fluids and placenta.

The American Sheep Industry Association said the infected sheep did not carry an official ear tag, which may complicate tracing. Before this finding, the US was on course to meet a World Organisation for Animal Health benchmark for self-declared scrapie freedom in January 2028.

USDA officials said the trade impact should be limited, as most countries restrict live imports from affected flocks rather than from the country as a whole. Producers are being urged to keep animals properly identified, use resistant breeding stock and continue participating in surveillance programmes.