Mad cow disease

Overview

Bovine spongiform encephalopathy (BSE), known colloquially as mad cow disease, is an animal disease. Animals become infected with prions (misfolded proteins) when eating contaminated meat-and-bone meal. The animals exhibit changes in behaviour and movement disorders. Eating meat contaminated by BSE can cause Creutzfeldt-Jakob disease (vCJD) in humans.

Symptoms

(In cattle)

• Behavioural changes
  • Agitation
  • Oversensitivity to light, touch, noise
• Movement disorders
  • Twitching, unsteady gait, falling
• Emaciation and reduced milk output
• The disease is always fatal

Causes and treatment

Causes

• Infection with prions (misfolded proteins) through eating contaminated meat-and-bone meal
• Incubation period
  • Years to decades
• In spite of the fact that BSE has been found in a considerable number of cattle, no vCJD has been diagnosed in Switzerland to date

Measures by the authorities

Risk of new BSE infections has been drastically reduced

• Since 2000, no meat-and-bone meal may be fed to ruminants anywhere in Europe
• Guidelines are regularly reviewed and amended if necessary
• Strict regulations
• The origin of meat products must be declared
• Tighter export provisions
• Faster diagnosis of the disease in livestock

What can I do myself?

• Avoid eating the brains, spinal cords, eyes and offal (intestine, liver, kidneys, sweetbread) and products that may contain such animal parts (e.g. sausages)
  • In Switzerland, these organs are removed from the carcasses of slaughtered cattle from a certain age and burned as a preventive measure
• Investigations seem to indicate that infectious prions can't be transmitted by eating muscle meat, but this hasn't been proven

Further information

Federal Food Safety and Veterinary Office, FSVO (Bundesamt für Lebensmittelsicherheit und Veterinärwesen, BLV)
www.blv.admin.ch/blv/en/home.html

Synonyms

mad cow disease, bovine spongiform encephalopathy, BSE