WASHINGTON: Discovered in Britain in 1986, mad cow disease destroys the brains of cattle and a similar, fatal disease can affect people who eat meat from infected cattle, according to scientists.

More than 160 people, mainly in Britain and other European countries, have died from the human disease, variant Creutzfeldt-Jakob Disease.

Mad cow disease, formally named bovine spongiform encephalopathy, or BSE, may have originated when cattle feed was mixed with pieces of sheep carcasses infected with scrapie, one of a family of brain-destroying diseases including BSE. Some researchers believe the disease arose spontaneously.

The first US case of mad cow disease was discovered in December 2003 in a Holstein dairy cow in Washington state. It originally came from a herd in Alberta, Canada.

The second US case and the first in a native-born animal was a Brahma crossbreed beef cow in Texas in November 2004.

Misshapen prion proteins on the surface of nerve cells, are blamed for causing mad cow disease. They replicate, form clumps and cause the brain to become spongy and wither.

Source: China Daily