|vCJD (variant Creutzfeldt-Jacob disease)||
Creutzfeldt-Jakob disease (CJD) is an illness of the nervous system that causes damage to the brain. (The disease is named after two German scientists). CJD is fatal, and there is no known cure.
CJD is caused by an abnormal protein (prion) that contaminates the nervous system. There are four different types of CJD. A new type of CJD, new variant CJD, now referred to simply as variant CJD (vCJD) was identified in 1996. Unlike sporadic CJD, it affects mainly people in their mid-twenties. There is clear evidence that variant CJD is caused by a prion – the same strain of infection that causes what is known as mad cow disease (bovine spongiform encephalopathy or BSE).
Definition from NHS Choices: vCJD