Kondo K
Department of Public Health, Hokkaido University School of Medicine, Sapporo, Japan.
Hokkaido Igaku Zasshi. 1997 Jan;72(1):27-36.
Prions (proteinaceous infectious particles) are responsible to subacute spongiform encephalopathies (SSE) in man and animals. Recent outbreak of bovine SSE (BSE), or mad cow disease in UK provoked concerns on its possible human hazards. A statement of the British Government in March 1996 upset the world, which was based on 10 cases of "new variant" form of Creutzfeldt-Jakob disease (CJD). Prion diseases in animals are often epizootic and may be spread to different species through various routes including ingestion of contaminated meats. It is possible that mad cow disease causes a CJD-like malady in man through a dietary route. human SSE include; 1) Classical CJD, which represents over 95% of the cases with SSE, dispersely sporadic in occurrence in 1 per million a year, with monotonously rising incidence rates with age, of which the origin of the prion is totally unknown. 2) Gerstmann-Sträussler-Scheinker's disease which is inherited dominantly due to various genetic variants of the prion. 3) Transmitted cases of CJD occurring due to the prion introduced through contaminated objects either directly to the brain or its coverings, or indirectly to the brain through peripheral organs. 4) Kuru occurring among the Fore people in Papua New Guinea, probably due to the prion spread by a dietary route in cannibalism. New variant CJD (vCJD) now totals 14 cases all observed in UK and is different from all of four, is encountered in a dispersely sporadic manner, is far younger at onset than classical cases, showing kuru-plaques. Prions from vCJD have physical-chemical properties similar to those from BSE. Countermeasures in Japan against human hazards of BSE include, 1) agent controls by means of quarantine, and 2) host controls. So far no vCJD-like case is observed in Japan. An emergent surveillance for CJD was introduced by the Ministry of Health and Welfare in July 1996. It obtained a total of 2,637 answers from 4,027 departments of neurology, psychiatry, etc throughout the country and identified 766 cases including 51 familial cases, but no case with vCJD.
朊病毒（蛋白质感染性颗粒）是人类和动物亚急性海绵状脑病（SSE）的致病因子。最近英国爆发的牛海绵状脑病（BSE），即疯牛病，引发了人们对其可能对人类造成危害的担忧。1996年3月英国政府的一份声明震惊了世界，该声明基于10例“新变异型”克雅氏病（CJD）。动物的朊病毒病通常呈流行状态，并可能通过包括摄入受污染肉类在内的各种途径传播给不同物种。疯牛病有可能通过饮食途径导致人类患上类似CJD的疾病。人类SSE包括：1）经典型CJD，占SSE病例的95%以上，每年散发性发病，发病率为百万分之一，发病率随年龄单调上升，其朊病毒的来源完全未知。2）格斯特曼-施特劳斯勒-谢inker病，由于朊病毒的各种基因变异而呈显性遗传。3）因朊病毒通过受污染物体直接进入大脑或其被膜，或通过外周器官间接进入大脑而发生的CJD传播病例。4）在巴布亚新几内亚的福尔人中出现的库鲁病，可能是由于在食人行为中通过饮食途径传播的朊病毒所致。新变异型CJD（vCJD）目前共有14例，均在英国发现，与上述四种情况均不同，呈散发性出现，发病年龄比经典病例年轻得多，表现为库鲁氏斑块。vCJD的朊病毒具有与BSE的朊病毒相似的物理化学性质。日本针对BSE对人类危害的对策包括：1）通过检疫进行病原体控制；2）宿主控制。到目前为止，日本尚未观察到类似vCJD的病例。1996年7月，厚生省引入了对CJD的紧急监测。它从全国4027个神经科、精神科等科室共获得了2637份回复，确定了766例病例，其中包括51例家族性病例，但没有vCJD病例。
