内蒙古和新疆地区蜱虫携带人畜共患病毒的病原生态学与分子流行病学研究

Ticks are transmission media and storage hosts for some important zoonotic viral diseases and animal epidemic diseases. There are more than 80 viruses, including African swine fever virus, severe fever with thrombocytopenia syndrome Bunya virus (SFTSV, or tick disease in China), Xinjiang hemorrhagic fever virus and forest encephalitis virus, have been discovered to be carried in ticks. Inner Mongolia and Xinjiang province, which are adjacent to many countries, not only belong to the “The Belt and Road” economic zone, but also are important pastoral areas of China with abundant resources of wild animals. On the other hand, however, there are potential threats from the cross board transmission and epidemics of new emerging viruses or zoonotic viruses in this region. Ticks are widely distributed in these areas, but studies on tick-borne virus have been impeded in this region, owing to limited background data is available. Therefore, based on the foundation of technical platform of viral metagenomics established in our previous research projects in ticks of Northwest China, the ultimate goal of the present proposal aims to investigate the pathogenic ecology and molecular epidemiology of tick-borne zoonotic virus in Inner Mongolia and Xinjiang province of China. To this end, ticks will be extensively collected form the prairies and host of livestock’s skins in the Inner Mongolia and Xinjiang areas, and tick-borne viruses will be analyzed by viral metagenomics technology, and an ecological database will be established. The potential viruses for zoonotic diseases and their biological significance will be further explored by amplifying complete viral gene sequences, virus isolation, as well as genetic and pathogenic analysis. By an accomplishment of comprehensive and systematic analysis of tick-borne virus from these two regions, it will allow us to identify novel potential viruses or zoonotic pathogenic viruses carried in ticks, and to provide pathogen ecological and molecular epidemiological data of tick-borne viruses in Inner Mongolia and Xinjiang, which may provide useful data for prevention and control of zoonotic viral diseases and foreign viral epidemics of tick-borne virus in Northwest China.

蜱虫是一些人畜共患及重要动物疫病病毒的传播媒介和贮存宿主，携带着非洲猪瘟病毒、新型布尼亚病毒和新疆出血热病毒等80多种病毒。内蒙古和新疆属于“一带一路”经济带，是我国重要牧区，其野生动物资源丰富，毗邻多国，存在着新发或人畜共患病毒病的跨境传入和流行的潜在威胁。蜱虫在这些地区分布广泛，但有关蜱媒病毒的研究报道甚少，本底数据匮乏。因此，本项目拟在课题组已建立的病毒宏基因组学平台和对西北地区蜱虫调研的基础上，广泛采集内蒙古和新疆地区蜱虫，对蜱虫携带的病毒进行宏基因组学分析，建立生态学数据库；并对潜在有人畜共患和生物学意义的病毒进行全基因序列扩增、病毒分离、遗传分析和致病性等研究。通过对这两个地区的蜱媒病毒进行全面系统的研究，以期发现潜在的新的或人畜共患致病性病毒，完善内蒙古和新疆地区蜱传病毒病原生态学和分子流行病学数据，为这一地区蜱媒病毒性人畜共患病和境外疫病的防控提供科学依据。

蜱虫是一些人畜共患及重要动物疫病病毒的传播媒介和贮存宿主，携带着非洲猪瘟病毒、新型布尼亚病毒和新疆出血热病毒等多种病毒。内蒙古和新疆属于“一带一路”经济带，是我国重要牧区，其野生动物资源丰富，毗邻多国，存在着新发或人畜共患病毒病的跨境传入和流行的潜在威胁。蜱虫在这些地区分布广泛，但有关蜱媒病毒的研究报道甚少，本底数据匮乏。针对此种情况，本研究在新疆4个地区（青河、富蕴、福海及乌苏）采集到2个属6种蜱虫，内蒙古4个地区（四子王旗，阿拉善左旗、右旗和左右旗交界处）采集到2个属5种蜱虫，利用病毒宏基因组学和宏转录组学等相关技术对蜱虫病毒组学与分子流行病学进行了研究。在8个蜱虫宏转录组文库中共获得了17个已知的病毒科和一些未分类的21种病毒，包括9种已鉴定的病毒和12种新病毒；在内蒙古蜱虫病毒宏基因组中共注释到20个已知的病毒科和未分类的病毒序列信息。这些发现包括一种新的阿拉善蜱白蛉病毒，内蒙古蜱虫鸽圆环病毒，以及在内蒙古的四子王旗首次发现了发热伴血小板减少综合征病毒（SFTSV）的存在；特别是获得了一株涉及公共卫生安全的内蒙古地区克里米亚-刚果出血热病毒（CCHFV）全基因组信息，揭示了在内蒙部分地区的绵羊及骆驼寄生蜱虫单样携带CCHFV阳性率为6.7%，宿主血清中的阳性率为39.2%。另外，为了后续CCHFV的防控，我们开展了基于CCHV病毒Gn和Np蛋白的昆虫杆状病毒表明展示疫苗和间接ELISA检测方法的研究。以上这些研究表现出这些地区蜱媒病毒的组成分布与多样性情况，阐明了蜱媒病毒在病毒进化过程中的演化历程，并揭示了部分蜱媒病毒可能存在跨区域、跨物种传播，这些研究为中国新疆和内蒙古地区蜱虫携带病毒本底情况，以及为防控公共卫生安全病毒的流行和扩散提供了重要的理论参考。