Bovine spongiform encephalopathy

Abstract

Bovine spongiform encephalopathy is an infectious disease of cattle that is transmitted through the consumption of meat-and-bone meal from infected cattle. The etiologic agent is an aberrant isoform of the native cellular prion protein that is a normal component of neurologic tissue. There currently are no approved tests that can detect BSE in live cattle.

Bovine spongiform encephalopathy and food safety

“…Only one strain, classical BSE, was responsible for the BSE epidemic and the associated epidemic of vCJD 8 . The atypical H-type and L-type strains typically occur in cattle over eight years of age, and appear to arise spontaneously 9,10 .…”

“…Iatrogenic transmission of vCJD remains a concern because retrospective analysis of tonsil and appendix specimens suggests that up to 1 in 4000 persons exposed during the UK epidemic may be a sub-clinical carrier 8,22 . Interna- Throughout the EU, cattle are individually and permanently identified, and each country has an electronic database recording the details, locations, movements and fate of all cattle.…”

“…Cases of TSE were also diagnosed in two domestic goats 20 and a number of domestic cats 8,18 . All these cases were attributed to ingestion of BSE prions in beef or processed feed.…”

“…The epidemic of BSE was first recognized in 1986 in the UK and was propagated by the rendering of dead cattle to produce meat-andbone meal (MBM) which was then included in feed for cattle 8 . The infection was spread elsewhere in the world by exports of cattle and contaminated MBM 9 .…”

“…Variant CJD is distinct from the most common human prion disease, sporadic CJD (sCJD), which occurs spontaneously in people, Under the Microscope including lifelong vegetarians 8 , between 55 and 70 years old 12 . Both forms of CJD are fatal.…”