July 15, 2004
July 15, 2004 -- Olivier Andreoletti and others from the National Veterinary School in Toulouse, France, recently reported in the medical journal, Nature Medicine, that he and colleagues have isolated very small quantities of prion from the muscle of sheep infected with scrapie under laboratory conditions.
The authors emphasized the finding did not mean that lamb or mutton posed a danger to humans. They also cautioned against drawing broader conclusions about other transmissible spongiform encephalopathies (TSE's) and other species based upon this research.
Dr. Paul Brown, a prion expert at the National Institutes of Health, added that after nearly 40 years of trying, no researcher has ever infected a healthy animal with a prion disease by injecting it into muscle tissue. This raises the question whether the small quantities found in this study represent an infectious dose. He and others point to the dramatic improvement in the sensitivity of new diagnostic technologies that make this type of research exciting.
The American Sheep Industry Association, along with other commodity and allied industry groups, continue to monitor all research regarding TSE's.