"Clusters" of CJD in Slovakia: the first laboratory evidence of scrapie.

Epidemic-like occurrence of Creutzfeldt-Jakob disease was observed in 1987 in Slovakia (Orava). Search for the cause of CJD focus indicated a coincidence of genetic and environmental risks in clustering patients. Since Spongiform Encephalopathies might be transmitted orally, (Bovine Spongiform Encephalopathy), the possibility of zoonotic source of CJD cases in Orava was also considered. A deficient knowledge about the occurrence of scrapie in Slovakia stimulated an examination of sheep with signs of CNS disorders in two flocks of Valasky breed in Orava. In one flock, neurohistopathological examination revealed in sheep brains lesions characteristic for scrapie. Frozen brain tissue of these animals were used for the detection of scrapie associated fibrils. They were found in 2 animals from the same flock. This is the first laboratory confirmation of scrapie in Czecho-Slovakia. The possible epidemiological and economical implications are emphasized.