People develop variant CJD from eating beef products contaminated with abnormal prions. The BSE ("mad cow disease") epidemic in the UK ran from 1985-1993 and is believed to have started either spontaneously in cows or from feed contaminated with sheep parts infected with scrapie, the sheep form of prion disease. Cattle in most countries are now screened for BSE, animal-protein by-products in the feed have been banned, and BSE surveillance programs have been created. While the beef supply is generally considered safe, eating solid muscle meat from grass-fed cows (usually labeled "organic") versus beef-derived products such as burgers and sausages may increase your safety. More cases of vCJD may continue appear due to the long incubation period.
