Mad cow disease is a fatal neurological disease that slowly destroys the brain and spinal cord (central nervous system) of cattle. It also is known as bovine spongiform encephalopathy, or BSE. BSE belongs to a family of debilitating brain diseases that can affect other animals bred for human consumption. And when humans eat boned meat and organs from these infected animals, they risk becoming infected as well.

Causes

Animal cells normally contain many kinds of proteins. Scientists think mad cow disease is caused by a change in some of these proteins caused by abnormal proteins called prions, but it is not clear how prions cause the change. Prions are not like bacteria or viruses that cause other infectious diseases; rather, they are infectious proteins.
Diseased prions are found in the brain, spinal cord, eye, and other tissues of the nervous system of affected animals or humans. When a cow is slaughtered, certain parts of it are used for human food and other parts are processed into animal feed. If an infected cow is slaughtered and its nerve tissue is used in cattle feed, other cows can become infected. People cannot get mad cow disease. However, in rare cases they may get a human form of mad cow disease called variant vCJD if they eat nerve tissue (the brain and spinal cord) of cattle that were infected with mad cow disease.

Symptoms

Symptoms in the animal include a change in attitude and behavior, gradual uncoordinated movements, trouble standing and walking,  and decreased milk production. Eventually the animal dies. Similar symptoms may develop in humans: muscle spasms, lack of muscle control, worsening problems with memory.
Symptoms may include:
Dementia and psychotic behavior.
Coordination problems. As the disease progresses, a person is no longer able to walk.
Coma.

Treatment

There is no cure for vCJD. Treatment includes managing the symptoms that develop as the disease progresses.