Hadlow W J, Kennedy R C, Race R E
J Infect Dis. 1982 Nov;146(5):657-64. doi: 10.1093/infdis/146.5.657.
A better understanding of the infectious process in scrapie was sought by studying the temporal distribution of virus in naturally infected Suffolk sheep. Virus was detected (by mouse inoculation) first in lymphatic tissues and intestine of clinically normal lambs (age, 10-14 months). Titers were generally low. Infection of the central nervous system was first detected in a 25-month-old clinically normal sheep whose nonneural tissues had moderate amounts of virus. In sheep affected with scrapie, similar amounts in nonneural tissues accompanied high concentrations in the central nervous system, notably in sites of severest neurohistologic changes. No virus was found in clinically normal high-risk sheep 54 to 104 months old. The early appearance of virus in tonsil, retropharyngeal and mesenteric-portal lymph nodes, and intestine suggests that primary infection occurs by way of the alimentary tract, either prenatally from virus in amniotic fluid or postnatally from virus in a contaminated environment.
通过研究病毒在自然感染的萨福克绵羊中的时间分布，来寻求对羊瘙痒病感染过程的更好理解。（通过小鼠接种）首先在临床正常羔羊（年龄10 - 14个月）的淋巴组织和肠道中检测到病毒。病毒滴度通常较低。在一只25个月大的临床正常绵羊中首次检测到中枢神经系统感染，其非神经组织中有适量病毒。在患有羊瘙痒病的绵羊中，非神经组织中的病毒量相似，同时中枢神经系统中病毒浓度很高，特别是在神经组织学变化最严重的部位。在54至104个月大的临床正常高风险绵羊中未发现病毒。病毒在扁桃体、咽后和肠系膜 - 门静脉淋巴结以及肠道中的早期出现表明，原发性感染是通过消化道发生的，要么是产前从羊水中的病毒感染，要么是产后从受污染环境中的病毒感染。
