Bovine spongiform encephalopathy and variant Creutzfeldt-Jakob disease: Background, evolution, and current concerns

The epidemic of bovine spongiform encephalopathy (BSE) in the United Kingdo m, which began in 1986 and has affected nearly 200,000 cattle, is waning to a conclusion, but leaves in its wake an outbreak of human Creutzfeldt-Jako b disease, most probably resulting from the consumption of beef products co ntaminated by central nervous system tissue. Although averaging only 10-15 cases a year since its first appearance in 1994, its future magnitude and g eographic distribution (in countries that have imported infected British ca ttle or cattle products, or have endogenous BSE) cannot yet be predicted. T he possibility that large numbers of apparently healthy persons might be in cubating the disease raises concerns about iatrogenic transmissions through instrumentation (surgery and medical diagnostic procedures) and blood and organ donations. Government agencies in many countries continue to implemen t new measures to minimize this risk.