Prion diseases are transmissible neurodegenerative disorders that include scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle and Creutzfeldt-Jakob disease (CJD) in humans. The principal component of the infectious agent responsible for these diseases appears to be an abnormal isoform of the host-encoded prion protein (PrP), designated PrP(Sc). Prion diseases are transmissible to the same or different mammalian species by inoculation with, or dietary exposure to, infected tissues. Although scrapie in sheep has been recognized for over 200 years, it is the recent epidemic of BSE that has centred much public and scientific attention on these neurodegenerative diseases. The occurrence of variant CJD in humans and the experimental confirmation that it is caused by the same prion strain as BSE has highlighted the need for intensive study into the pathogenesis of these diseases and new diagnostic and therapeutic approaches. The existence and implications of subclinical forms of prion disease are discussed.

中文翻译：

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亚临床病毒感染。

on病毒疾病是可传播的神经退行性疾病，包括绵羊瘙痒病，牛海绵状脑病（BSE）和人类克雅氏病（CJD）。引起这些疾病的传染原的主要成分似乎是宿主编码的ion病毒蛋白（PrP）的异常同工型，称为PrP（Sc）。通过对感染的组织进行接种或饮食接触，病毒可以传播给相同或不同的哺乳动物。尽管人们已经认识到绵羊的瘙痒病已有200多年的历史了，但最近疯牛病的流行还是将许多公众和科学注意力集中在这些神经退行性疾病上。变异型克雅氏病在人类中的发生以及由与疯牛病相同的pr病毒株引起的实验证实，突出表明需要深入研究这些疾病的发病机理以及新的诊断和治疗方法。讨论了ion病毒亚临床形式的存在及其意义。