[Natural history of transmissible subacute spongiform encephalopathy (TSSE)]

Sheep Scrapie is the archetype of ESST It has been described for more than 200 years but the first scientific papers were published less than 60 years ago. The link between doctors and veterinary surgeons enabled our knowledge to develop. First, a Slow Virus was evoked, then Hadlow DVM (USA) suggested using brain filtrates from deceased patients of Kuru in order to inoculate primates or small rodents; this was carried out by the team of D.C. Gajdusek. The complete absence of immune reaction has made the label "slow Virus" give way to "Non Conventional Transmissible Agent" (NCTA). The few human cases of ESST have all been transmitted to mice, rats, hamsters... S.B. Prusiner (San Francisco) has given us an enormous boost with the notion of Prion, a protein molecule derived from an ordinary small membrane protein. Having recourse to transgenic mice has enabled American and European teams to demonstrate the essential role of genetics in the forming of the Transmissible Agent which is certainly Not Conventional. Those responsible for the Health of Cattle in U.K. will not contradict us. Future Research will be fascinating and will open a new chapter in the Medical Science concerning Mammals.