二十世纪末,在人们已经熟知的包括细菌、病毒、真菌和寄生虫在内的人类病原谱中,又增添了一种全新的病原体—朊粒(prion)。朊粒是一个超出经典病毒学和生物学的全新病原学概念,是一种不含核酸的蛋白质感染性粒子。由其引起的疾病称朊粒病,主要引起人和动物中枢神经系统退化性疾病,即传染性海绵状脑病(transmissible spongiform encephelopa- At the end of the twentieth century, a new pathogen, prion, has been added to the well-known spectrum of human pathogens, including bacteria, viruses, fungi and parasites. Prion, a brand new etiology beyond classical virology and biology, is a protein-free, particle-free protein. The disease caused by it is called prion disease, which causes mainly degenerative diseases of the central nervous system of humans and animals, that is, transmissible spongiform encephelopa-