[Epidemiology and surveillance system of prion disease in Japan].

The current surveillance system by the Creutzfeldt-Jakob disease (CJD) Surveillance Committee, Japan, started in April 1999, and 836 patients with prion diseases had been registered until September 2006, including sporadic CJD (78 %), inherited prion disease (14 %), and infectious prion disease (8 %). The infectious prion disease included a patient with variant CJD and 68 patients with dura mater graft-associated CJD (dCJD). Combined with the dCJD patients identified by previous surveillance systems, the total number of dCJD was counted to be 124.