After learning about prion diseases in class and having heard of Mad Cow Disease before, but never truly understanding it, I decided to investigate further. Mad Cow Disease, otherwise known as Bovine spongiform encephalopathy, became an epidemic in the United Kingdom in the late 1980’s. It has many similarities to Scrapie and Kuru. All cause degeneration of the brain and lead to behavioral and neurological changes usually ending in death. Mad Cow Disease got its common name from the symptoms that develop in cows. Infected bovines had an increase in aggression and would react excessively to noise or touch. This caused farmers to believe that they had gone “mad.”
The true reason that Mad Cow Disease became such a worldwide phenomenon is that humans began to be infected and the disease was almost always fatal. The frenzy and fear associated with the disease led the European Union to ban the exportation of British Beef in 1996. This ban lasted for ten years. This ban may have saved thousands of lives because much of that beef may have been infected. Just like with Kuru and Scrapies, the disease was transmitted through the consumption of infected brain and spinal cord. Although cows are usually herbivores, the British cattle had been fed ground up cow remains from the slaughtering process. This is very similar to the spread of Scrapie among sheep and goats. The general public began to panic when the disease spread to humans. Slaughtering practices at the time allowed for some traces of nervous system tissue to be included in the mince and beef that was to be consumed by humans. When a human bought and consumed a beef product which contained this infected nervous system tissue, the misfolded cow prions were able to affect healthy human prions in the consumer’s brain. In humans, the disease is known as Variant Creutzfeldt Jakob disease. The only way to end the epidemic was to ban the exportation of British meat, exterminate nearly all British cattle that hadn’t already been slaughtered, and create new regulations for the feeding and slaughtering of cattle. Nearly 200 people died from contracting the disease, but new regulations have put Bovine spongiform encephalopathy to rest.
It was really interesting to learn more about the Mad Cow Disease. I wonder whether ethics was an issue that came up at the inception of the disease – it seems like this disease was in a way caused by humans because they were the ones to feed herbivores meat products they would never otherwise consume.