The Facts
Bovine spongiform encephalopathy (BSE), commonly known as "mad cow disease," is a fatal disease that strikes the nervous system of cattle. Currently no vaccine or treatment exists for it, and affected animals display a variety of neurological symptoms before they die. (Think of television reports showing cows having trouble standing up.) An animal with outward symptoms of BSE may survive for 2 to 6 months, though it may have carried the disease for up to 6 years. BSE has a longer-than-usual incubation period (i.e., the time between infection and the development of symptoms), ranging from 3 to 6 years - a long period of time for it to remain undetected.
BSE is a disease that only cows develop; however, it is related to a disease that affects humans, called Creutzfeldt-Jakob disease (CJD). CJD occurs due to a spontaneous genetic mutation that occurs in one in every million individuals. Recently, a new form of CJD has emerged and has been called variant CJD (vCJD). This new form of the disease has been linked to the consumption of meat products infected with BSE.