Some problems of diagnosis of the spongiform encephalopathies in ruminants.

The difficulties of a positive diagnosis in the spongiform encephalopathies based only on epidemiological and clinical data are briefly reviewed. However, in B.S.E. as in scrapie, the epidemiology and the clinical data may frequently suggest these diseases. The main diseases which must be taken into account in the differential diagnosis of both spongiform encephalopathies are discussed and the criteria of the differential diagnosis are tabulated.