What is Scrapie?
Scrapie is a fatal neurodegenerative disease caused by a misfolded protein known as a prion. It was first introduced in 1947 into a flock in Michigan and has since spread throughout the United States. It is in the family of diseases known as a transmissible spongiform encephalopathies. These include diseases such as bovine spongiform encephalopathy (BSE), Chronic wasting disease (CWD) in deer and Creutzfelt-Jakob disease in humans. Scrapie is the oldest known TSE and under natural conditions only affects sheep and goats with sheep being more commonly affected.
How is it transmitted?
Sheep and goats are typically infected at a very young age, however, signs associated with this disease take years to manifest and usually do not show up until 2-6 years of age. It is thought to spread from mother to offspring via infected placenta and associated fluids where the protein is found in the highest concentrations. It is also found in smaller concentrations in feces, saliva and urine. These tissue and fluids can infect the environment and it can remain infective for years. Adult animal can become infected after exposure, but it is less common.
What are the signs of Scrapie?
This disease received it's common name, Scrapie, from one of the clinical signs associated with the disease. It can cause intense pruritis (itching) and a scraping off the wool on the body, however, a variety of clinical signs are associated with this disease and can include:
- Weight loss and progressive wasting despite a normal appetite
- Aggression and behavior changes
- Neurologic signs such as star gazing, incoordination (ataxia), bunny hopping, high stepping of front limbs and head pressing.
- Biting at feet and legs
- Lip smacking
- Death
If you are concerned your animals may be infected with scrapie, contact your veterinarian so they can perform a risk analysis.
Is Scrapie treatable?
No. Scrapie is a fatal disease and no treatment has been found to be effective.
Can Scrapie affect people?
No. There is currently no data to show that scrapie can be transmitted to humans, however, meat from a diagnosed animal is not considered safe to eat due to similar diseases affecting humans.
Do genetics play a role?
Yes, they do. In sheep, the animal's genotype strongly influences the chances of developing the disease. In goats, genetic susceptibility is less understood but does play a role.
Scrapie Eradication Program
The United States Department of Agriculture's Scrapie Eradication Program is a program designed to help eliminate Scrapie in the US's sheep and goat herds. Sheep and goats owners and producers should be registered with the Scrapie program and have a Flock ID number, which is also sometimes called a Scrapie ID number. For additional information on the Scrapie Eradication Program please visit USDA's Scrapie page.
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