Bovine spongiform encephalopathy, chronic wasting disease, scrapie, and the thre

August 31, 2006

2359101

Curr Neurol Neurosci Rep. 2002 Nov;2(6):488-95.

Bovine spongiform encephalopathy, chronic wasting disease,

scrapie, and the threat to humans from prion disease epizootics.

* Bosque PJ.

Division of Neurology, Denver Health Medical Center, 700 Delaware

Street, M/C 4000, Denver, CO 80204-4507, USA. patrick.bosque

Ongoing endemics and epidemics of prion disease afflict several

species of ruminants regularly consumed by humans. Bovine spongiform

encephalopathy (BSE) is epidemic in British cattle, and is now found

in the cattle of more than 20 countries. A large, and apparently

growing, epidemic of chronic wasting disease plagues deer and elk in

North America. Finally, scrapie has been endemic in the sheep of most

countries for many decades. It was once assumed that humans were not

susceptible to these ruminant forms of prion disease, but an outbreak

of a new form of Creutzfeldt-Jakob disease (CJD) among young Britons,

almost certainly due to dietary exposure to BSE-contaminated beef, has

disproved this supposition. Although all prion diseases share the same

fundamental pathologic mechanism, transmission between species is

sometimes inefficient. The basis of this " species barrier " is

incompletely understood, but interspecies differences in the amino

acid sequence of the prion protein and the strain of prions involved

play critical roles. Reliable experimental models for determining the

resistance of humans to animal prion diseases do not yet exist. It is

possible that animal to human transmission of prion disease may

manifest as CJD with unusual characteristics, but this is not

necessarily the case. In the absence of a reliable means for

determining the susceptibility of humans to animal prion disease,

measures to minimize human exposure to animal prions should be emphasized.

PMID: 12359101 [PubMed - indexed for MEDLINE]

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