BSE
What is it?
BSE (Bovine Spongiform Encephalopathy) M also known as ‘mad cow disease’ M is caused by an abnormal, infectious protein known as a prion. The late 1980s and early ’90s UK BSE crisis was one of the most devastating disease epidemics that has ever struck the European cattle population.
History
The first animal fell ill with BSE in Britain in 1984. Over the next few years, the epidemic spread nationwide. To date, there have been around 180,000 confirmed cases in cows and another 4.7 million adult animals were destroyed during the eradication programme. BSE is now found in at least 25 countries and is estimated to have cost European Union taxpayers P65 billion.
Source
In 2000, a government commissioned inquiry found that BSE developed into a disaster because of the feeding of cows, who are natural herbivores, with the remains of other cows. The feed also included the ground and cooked body parts of sick and injured animals taken from the slaughtering process.
Symptoms in animals
BSE causes a spongy degeneration in the brain of cattle. It has an incubation period of about four years, before symptoms appear. They include changes in mental state and abnormalities of posture, movement and sensation.
Symptoms in people
Anxiety and depression are often the first symptoms of the human form of BSE, known as variant Creutzfeldt Jakob Disease N CJDO. As in cattle, it affects the nervous system, causes a degenerative brain disease and is invariably fatal. There may be pain and strange sensations in the face and limbs. Months later, there might be jerkiness in movement, unsteadiness in walking, progressive dementia and, eventually, loss of ability to move or speak.
Routes of transmission
VCJD is thought to be acquired through exposure to BSE by eating contaminated beef products. A total of 167 cases of CJD have been reported in the UK the last one in 2008O, of which 164 have proved fatal. Doctors and scientists have warned that a second wave of CJD could sweep Britain over the next two to three decades, as it has emerged that the long incubating illness infected a patient with a different gene type from previous British victims. A major complicating factor of prions are their virtual indestructibility. They cannot easily be destroyed by heat treatment. Scientists have also confirmed that CJD can be passed from person to person through contaminated medical equipment and blood
transfusion.
transfusion.
Treatment
From 1988, the UK government began introducing various restrictions on the types of foods that could be fed to farmed animals and what parts could go into the food chain. There was a mass slaughter of adult animals judged to present a risk to human health, and farmers were compensated (Over Thirty Month Scheme). Young calves were also killed (Calf Processing Scheme) as a measure to protect the devastated trade in cattle meat. The EU banned exports of live cattle and cattle meat from Britain but, over the years, the various restrictions have been eliminated, with exports to Europe re-commencing in 2006.