ABSTRACT

Chronic wasting disease (CWD) affects a broad array of cervid species and continues to be detected in an expanding geographic range. Initially introduced into the Republic of Korea through the importation of CWD-infected elk (Cervus canadensis), additional cases of CWD were subsequently detected in farmed Korean elk and sika deer (Cervus nippon). Wild and farmed sika deer are found in many regions of Asia, North America, and Europe, although natural transmission to this species has not been detected outside of the Republic of Korea. In this study, the oral transmission of CWD to sika deer was investigated using material from CWD-affected elk. Pathological prion (PrP^CWD) immunoreactivity was detected in oropharyngeal lymphoid tissues of one sika deer at 3.9 months post-inoculation (mpi) and was more widely distributed in a second sika deer examined at 10.9 mpi. The remaining four sika deer progressed to clinical disease between 21 and 24 mpi. Analysis of PrP^CWD tissue distribution in clinical sika deer revealed widespread deposition in central and peripheral nervous systems, lymphoreticular tissues, and the gastrointestinal tract. Prion protein gene (PRNP) sequences of these sika deer were identical and consistent with those reported in natural sika deer populations. These findings demonstrate the efficient oral transmission of CWD from elk to sika deer.

摘要

慢性消耗性疾病（CWD）影响着各种各样的宫颈物种，并在不断扩大的地理范围内继续被发现。最初通过进口受CWD感染的麋鹿（加拿大鹿）引入大韩民国，随后在养殖的韩国麋鹿和梅花鹿（Cervus nippon）中发现了更多的CWD病例。在亚洲，北美和欧洲的许多地区都发现了野生和养殖的梅花鹿，尽管在大韩民国以外尚未发现到该物种的自然传播。在这项研究中，使用受CWD影响的麋鹿的材料研究了CWD向梅花鹿的口腔传播。病理性pr病毒（PrP ^CWD）接种后3.9个月（mpi）在一只梅花鹿的口咽淋巴组织中检测到了免疫反应性，在10.9 mpi的第二只梅花鹿中检测到了更广泛的分布。其余四只梅花鹿在21至24 mpi之间发展为临床疾病。对梅花鹿中PrP ^CWD组织分布的分析表明，它们在中枢和周围神经系统，淋巴网状组织和胃肠道中广泛沉积。这些梅花鹿的蛋白基因（PRNP）序列与天然梅花鹿种群中报道的序列相同且一致。这些发现证明了CWD从麋鹿到梅花鹿的有效口腔传播。