What is it? A chronic, degenerative disorder that affects the central nervous system of cattle.
What it does: Kills brain cells, creating gaps in tissue and giving the brain a sponge-like appearance.
Ways it is transmitted: Cow to calf; spontaneously; by eating ruminant feed.
Human form of BSE: Variant Creutzfeldt-Jakob disease (vCJD).
How people contract the vCJD: By eating the meat, particularly brain and spinal cord, from infected animals.
Symptoms: Memory loss, mood swings and lack of co-ordination, followed by shakiness, dementia and paralysis.