Diseases Related to Bovine Spongiform Encephalopathy

May 3, 2004

Scrapie: Bovine spongiform encephalopathy (BSE) or “mad cow disease” appears to have originated from scrapie, an endemic spongiform encephalopathy of sheep and goats that has been identified in Europe since the mid-18th century. Scrapie is a fatal, degenerative disease affecting the central nervous system of affected animals.

Chronic Wasting Disease (CWD): Chronic Wasting Disease is a transmissible spongiform encephalopathy (TSE) affecting elk and deer (cervids) in North America. It is a degenerative neurological illness that has affected both farmed and wild cervids in the United States, and has impacted the hunting and wildlife industries, as well as domestic and international markets for farmed cervids and cervid products. During the approximately two decades of monitoring, researchers have not found any evidence that CWD can be transmitted to domestic cattle under natural conditions, nor is it known to have transferred to other animals or people. Ongoing experiments involving oral exposure and contact exposure on heavily CWD contaminated sites have not resulted in infection of cattle.

Creutzfeldt-Jakob Disease (CJD): Creutzfeldt-Jakob Disease is a type of prion disease that primarily targets the nervous system in affected humans and animals. Prion diseases can be sporadic (spontaneous), transmitted by infection or inherited. They are characterized by the presence of microscopic vacuolization of the brain tissue, called spongiform degeneration, and of an abnormal form of a protein, called prion protein, which is a normal component in brain and other tissues.

Variant Creutzfeldt-Jakob Disease (vCJD): Variant Creutzfeldt-Jakob Disease is the strain associated with BSE and was first reported in the United Kingdom in 1996. It predominantly affects younger people, generally those under the age of 30. In April 2002, the Florida Department of Health and the Centers for Disease Control announced the discovery of a likely case of vCJD in a 22 year-old Florida resident who had previously lived in the UK.

Sources: The Centers for Disease Control and the U.S. Department of Agriculture.