[Bovine spongiform encephalopathy and Creutzfeldt-Jakob disease. Current questions].

The occurrence of Creutzfeldt-Jakob disease (CJD) in two teenagers and four dairy farmers in the United-Kingdom has focused attention on the possibility of a causal link between bovine spongiform encephalopathy (BSE) and Creutzfeldt-Jakob disease. The BSE epidemic was initiated by the inclusion in the cattle feed of the ruminant-derived protein in 1981/1982. A feed ban of the ruminant-derived protein in 1988 prevented further transmission of the infective agent to cattle by this route. However cases in animals born some years after the feed ban suggest that there has been some continued leakage of BSE infected material into animal feed (and perhaps maternal transmission?). To protect public and animal health, measures have been taken in the United Kingdom, especially prohibition of specified bovine offals in 1989 (extending this ban to thymus and intestine of calves slaughtered for human consumption in 1994). These measures are considered as minimizing the risk of BSE infection. Although the BSE linked risk factors are probably unique to the United Kingdom, it seems necessary to have the same regulations for the calves imported from this country. More, it is crucial that the ongoing surveillance programme of CJD in Europe is sustained.