I know this is considered to be old news, however the problem in the United Kingdom is not over yet. It has caused some very severe problems for farmers in the UK. It has also resulted in some trade relations problems between the UK and the rest of the world.
What is Mad Cow Disease?
It is a disease of the brain that causes cattle to slowly go crazy. The cattle become very unstable and can't stand up, act unpredictable, and eventually, they die. The disease basically destroys the brain.
It is officially called Bovine Spongiform Encephalopathy (BSE). Encephalopathy means that damage is occuring in the brain itself. Spongiform is the term used to describe what happens to the cow's brain. When a cow's brain is removed at autopsy the laboratory finds the diseased parts of the brain to be spongy in appearance. The first well-documented case of BSE was reported in 1986.
Mad Cow Disease or BSE is caused by a prion (proteinaceous infectious particle). This term is an acronym coined by Dr. Stanley Prusiner. This disease and others like it are transmitted by a protein. These diseases are very unusual. Viruses, bacteria, fungi, or parasites do not cause these diseases. Humans can also get Spongiform Encephalopathies (ex. kuru, Creutzfeldt-Jakob disease (CJD), and Gerstmann-Straussler-Scheinker syndrome).
This prion now has a name: PrP. PrP is found in a normal form in all animals. An altered form of PrP (PrP-sc) is what causes BSE. Cattle feed containing PrP-sc from sheep is believed to be the source of the infection in the cattle. To boost the protein content of cattle feed, manufacturers of feed placed sheep parts in the feed. Sheep also can get a spongiform encephalopathy called Scrapie. It is currently believed that somehow PrP-sc changed enough to cause infection in cattle. The use of sheep in cattle feed was banned in 1989. However, farmers continued to feed cattle the sheep-containing feed well into the 1990s.
Should We Be Concerned?
There is no clear-cut answer to that question. Some current experiments have shown that BSE-infected beef when fed to sheep can cause BSE. A number of carnivores in various British zoos have also developed BSE when fed presumably BSE-contaminated beef. In other words BSE can cause infection in other animals besides cattle.
No one knows for sure if humans can get BSE from this beef. However, in March of 1996, ten cases of a different form of Creutzfeldt-Jakob disease (CJD) were reported in humans in Britain. The average age of these patients was 28 and the patients did not have the same symptoms normally seen in
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