Animal Diseases

Bovine Spongiform Encephalopathy (BSE)

Bovine spongiform encephalopathy, commonly called "mad cow disease" or BSE, is a fatal degenerative disease of the central nervous system in cattle.

To date, there have been only three cases of BSE found in the United States after massive testing program and continued monitoring.

Consumers should keep several facts in mind:

Because of the United States' testing programs and cattle feeding practices, an outbreak on the scale of that which occurred in Great Britain is virtually impossible. Our system was designed to catch the isolated cases that are likely to occur and prevent the disease from spreading from those isolated cases. When we find a case, it is evidence that our system works – not that it has broken down.

The human health risk from this case is infinitesimal. The risky parts of the animal went into inedible products, not the animal or human food chain.

Milk does not contain the prions that science believes cause BSE. Dairy products are safe. Likewise, muscle tissue – meat – is generally safe because the prions are not found there.

In addition to the rendering processes and feeding practices that Great Britain used and so, unknowingly spread the disease, British people were eating different dishes than we in the U.S. do. Dishes and sausages containing brains and other organ meats that may have nervous tissue – and prions – were common in Great Britain.

Prevention
The United States takes a multi-pronged approach to preventing BSE: banning certain imports, banning suspect feed ingredients, testing for the disease, banning nonambulatory animals from slaughter, and banning risky animal tissues from human food.

Symptoms
Clinical signs of BSE may include behavioral changes, abnormal posture, decreased milk production and more.

Possible Causes
The leading theory is that the infectious agent is not a bacteria, virus, or other microorganism. Rather, many scientists believe that proteins in the animal's brain called prions that somehow become abnormal.

New-Variant Creutzfeldt-Jakob Disease
This new human disease has been linked to BSE. Although scientists are not in complete agreement as to what causes either disease or how the diseases are transmitted.

Transmissible Spongiform Encephalopathies
Transmissible spongiform encephalopathies are a family of central nervous system diseases that afflict cattle, sheep, cats, and humans.

Resources
Links to federal agencies and international organizations providing information on bovine spongiform encephalopathy.