Variant Creutzfeldt-Jakob disease (vCJD) is a fatal type of prion disease. Bovine spongiform encephalopathy (BSE) is a prion disease that affects cows. There is evidence that this illness can be transmitted to humans, producing vCJD. This illness is often called mad cow disease.


It is generally believed that vCJD is caused by infectious proteins called prions. Prions are normal proteins in the body. If these prions fold up differently than normal, they may transform into the protein that causes the illness. The build up of abnormal prions may be linked to the brain damage associated with vCJD.

The Nervous System
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Risk Factors

Variant CJD is more common in younger people. Other factors that may increase your chance of getting vCJD include exposure to prion-containing tissue. This may occur from:

  • Eating beef from infected cows
  • Receiving a blood transfusion from someone who had the disease


After you are exposed, it can take up to 20 years until symptoms develop. When symptoms develop, they usually follow these 3 phases:

  • Early phase (0-6 months)—psychiatric symptoms, such as depression, anxiety, withdrawal, memory problems, and difficulty pronouncing words
  • Middle phase—neurological symptoms predominate, such as abnormal gait, problems with coordination, muscle jerks and stiffness, and impaired speech
  • Late phase—muteness, immobility


Your doctor will ask about your symptoms and medical history. A physical exam will be done. Tests may include:

  • Blood tests
  • Electroencephalogram (EEG) to record the electrical activity of the brain
  • Lumbar puncture—to evaluate the cerebrospinal fluid that protects the brian and spinal cord
  • Brain biopsy
  • Tonsillar biopsy

Imaging tests take pictures inside your body structures. Imaging tests may include:

In many cases, a final diagnosis is not determined until an autopsy is completed after death.


Currently, there is no cure for vCJD. Treatment is primarily supportive, maximizing function and minimizing discomfort.


To reduce your chance of getting vCJD, avoid beef products, particularly processed meat like sausages and hot dogs, or beef items containing brain, spinal cord, or bone marrow.

About 200 worldwide cases of vCJD have occurred to date. Most of these were associated with beef consumption in the United Kingdom. There is a great deal of controversy regarding the safety of US beef. BSE has been detected in the US. However, no cases of vCJD have been attributed to eating US beef. US patients with vCJD were found to have obtained it outside of the US.

Revision Information

  • Reviewer: Rimas Lukas, MD
  • Review Date: 05/2016 -
  • Update Date: 06/02/2014 -