Cattle affected by BSE experience progressive degeneration of the nervous system. Affected animals may display changes in temperament, such as nervousness or aggression, abnormal posture, incoordination and difficulty in rising, decreased milk production, or loss of body weight despite continued appetite.
Affected cattle die.
There is neither any treatment nor a vaccine to prevent the disease. Following the onset of clinical signs, the animal s condition deteriorates until it either dies or is destroyed. This process usually takes from 2 weeks to 6 months. Most cases in Great Britain have occurred in dairy cows between 3 and 6 years of age. The human diseases are very rare and occur sporadically worldwide at a rate of about one case per one million people.