Fatzer R, Vandevelde M
Nationales Zentrum für spongiforme Enzephalopathien, Institut für Tierneurologie, Bern, Schweiz.
Wien Med Wochenschr. 1998;148(4):78-85.
Transmissible spongiform encephalopathies in animals are known for centuries. In particular scrapie in sheep and goats occurs worldwide; it spreads as a natural disease and is genetically controlled. Chronic wasting disease (CWD) in the United States (Wyoming and Colorado) also spreads as natural disease among free ranging and captive elk and mule deer. In contrast, transmissible mink encephalopathy (TME) of mink in fur producing farms is caused by contaminated feed; the source of this food contamination is still controversial. The only occurrence of a TSE in an avian species was reported from a flock of ostriches in a German zoo. The origin of the outbreak of bovine spongiform encephalopathy (BSE) in Great Britain could be traced back to feeding concentrates containing animal proteins contaminated with the agent of sheep scrapie. BSE was introduced into other countries, e.g. Switzerland and France, through the import of contaminated feeds from Great Britain. In addition, sporadic cases of TSE occurred in 10 other species, in particular domestic cats and zoo animals, e.g. antelopes and large cats. The diagnosis is based on the neuropathological examination of the brain as well as the demonstration of the disease specific protease resistant prion protein (PrPres). The first measures against the disease aim at eliminating the risk factors. The most important is the prohibition of feeding animal protein concentrates to ruminants. Thanks to this measure the incidence of BSE diminished remarkably. To protect consumers of beef products, in countries with BSE the potentially infectious organs of all cattle are confiscated at slaughter. Yet, in Great Britain this measure was introduced only at a point of time when BSE had already spread all over the country. Therefore, there is a strong probability of an exposition of consumers of beef with the BSE agent, which might have caused the new variant of Creutzfeldt-Jakob disease (nvCJD).
动物的传染性海绵状脑病已为人所知达数百年。特别是绵羊和山羊的痒病在全球范围内都有发生；它作为一种自然疾病传播，并且受基因控制。美国（怀俄明州和科罗拉多州）的慢性消耗病（CWD）也作为自然疾病在自由放养和圈养的麋鹿及骡鹿中传播。相比之下，毛皮养殖场水貂的传染性水貂脑病（TME）是由受污染的饲料引起的；这种食物污染的来源仍存在争议。唯一一例鸟类发生的传染性海绵状脑病是在德国一家动物园的一群鸵鸟中报道的。英国牛海绵状脑病（BSE）疫情的源头可追溯到喂食含有被绵羊痒病病原体污染的动物蛋白的浓缩饲料。BSE通过从英国进口受污染的饲料传入其他国家，如瑞士和法国。此外，在其他10个物种中也出现了散发性的传染性海绵状脑病病例，特别是家猫和动物园动物，如羚羊和大型猫科动物。诊断基于对大脑的神经病理学检查以及对疾病特异性蛋白酶抗性朊病毒蛋白（PrPres）的检测。针对该疾病的首要措施旨在消除风险因素。最重要的是禁止给反刍动物喂食动物蛋白浓缩物。由于这一措施，BSE的发病率显著下降。为了保护牛肉产品消费者，在有BSE的国家，所有牛的潜在感染性器官在屠宰时被没收。然而在英国，这一措施直到BSE已经在全国蔓延时才实施。因此，牛肉消费者很有可能接触到BSE病原体，这可能导致了新型克雅氏病（nvCJD）。
