Bunyavirus and Paramyxovirus infections at the interface between wildlife, livestock and humans in Nigeria and Cameroon

在尼日利亚和喀麦隆，存在野生动物和牲畜与人类重叠的地区，这增加了人畜共患病原体的传播风险。这些地区包括有牲畜市场和后院农场的城市地区，以及果蝠的城市繁殖和休息场所，果蝠被捕杀并作为丛林肉出售。市政基础设施差和人口缺乏卫生知识增加了这些风险。因此，将评估果蝠、啮齿动物、大鼠、鼩鼱、青蛙、蟾蜍和蜥蜴对人畜共患的布尼亚病毒和副粘病毒，特别是裂谷热病毒（RVFV）和亨尼帕样病毒（HNLV）的潜在储存功能。第一步，将使用“同一个健康”方法，确定小反刍动物（RVFV）和猪（HNLV）的血清患病率，以揭示虫媒病毒和蝙蝠相关感染的潜在热点。喀麦隆裂谷热病毒发病率的数据已经有了，而尼日利亚的裂谷热病毒情况和是否存在高传染性乙型肝炎病毒感染还有待确定。在潜在的高感染风险地区，将收集和检测上述物种的样本，以利用分子诊断和血清学方法发现持续或克服布尼亚和副粘病毒感染。此外，将使用相同的分子诊断和血清学方法检查与这些潜在宿主物种有过接触的人的样本（通过问卷确定）。在拟建项目的第二部分，将用RVFV分离株在体外感染来自上述潜在宿主的细胞系，并使用HNLV转录和复制能力强的病毒样颗粒（trvlp）获得这些物种的易感性证据。弗里德里希-吕弗勒研究所（FLI）提供蝙蝠（埃及Rousettus aegyptiacus， Eptesicus sertinus）和各种啮齿动物和其他物种（例如，光斑鼠、黑线鼠、褐家鼠）的细胞系，合作伙伴（Drosten教授，波恩，Essbauer博士，慕尼黑）可以提供更多的果蝠和啮齿动物细胞系。将对果蝠（Rousettus aegyptiacus）、大鼠（Rattus Rattus）和田鼠以及青蛙（Xenopus laevis）进行裂谷热病毒体内侵染研究，以确定这些物种的易感性、发病机制、感染过程和病毒脱落情况。这项工作将在国际自由研究所和七个非洲伙伴（包括五所大学）之间的密切合作下进行，其中包括使用综合课程培训五名非洲和两名德国博士/博士生，在伙伴国家举办关于项目相关问题的年度讲习班，以及非洲博士生在国际自由研究所进行两次为期6个月的研究访问。一个指导小组将在内部稳步监测进展情况，以确保信息和化验数据的不断流动，以及方案和样品/试剂的分发。

In Nigeria and Cameroon, there are overlapping areas of wildlife and livestock animals and humans, which poses an increased transmission risk for zoonotic pathogens. These include urban areas with livestock markets and backyard holdings and urban breeding and resting-grounds of fruit bats, which are hunted and sold as bushmeat. These risks are increased by poor municipal infrastructures and the lack of hygienic knowledge among the population. Therefore the potential reservoir functions of fruit bats, rodents, rats, shrews, frogs, toads and lizards for zoonotic bunya- and paramyxoviruses in general, and for Rift Valley fever virus (RVFV) and Henipa-like viruses (HNLV) in particular will be assessed. In a first step, using a One Health approach, seroprevalence rates will be determined in small ruminants (RVFV) and pigs (HNLV) to reveal potential hot spots for arboviral and bat-associated infections. Data for the RVFV incidence in Cameroon are already available, while the RVFV situation in Nigeria and the presence of HNLV infections will have to be determined. In potentially high infection risk areas samples from the above species will be collected and tested to reveal persistent or overcome bunya- and paramyxoviruses infections using molecular diagnostics and serological methods. In addition, samples from humans with contacts to these potential reservoir species (as determined by a questionnaire) will be examined using the same molecular diagnostic and serological methods. In a second part of the proposed project cell lines derived from the above potential reservoir hosts will be infected in vitro with RVFV isolates and by using HNLV transcription and replication competent virus like particles (trVLPs) to obtain evidence for a susceptibility of these species. Cell lines from bat (Rousettus aegyptiacus, Eptesicus serotinus) and various rodent and other species (e.g. Myodes glareolus, Apodemus agrarius, Rattus norvegicus) are available at the Friedrich-Loeffler-Institut (FLI) and more fruit bat and rodent cell lines can be supplied by cooperation partners (Prof. Drosten , Bonn, Dr. Essbauer, Munich). In vivo challenge studies of fruit bats (Rousettus aegyptiacus), rats (Rattus rattus) and voles as well as frogs (Xenopus laevis) with RVFV will be carried out to determine the susceptibility, pathogenesis, the course of infection and virus shedding of these species. This work will be carried out in close collaboration between the FLI and seven African partners (including five universities) which includes training of five African and two German PhD/doctoral students using integrated curricula, annual workshops on project-related issues in partner countries and two 6-month long research visits of African PhD students at the FLI. Progress will steadily be monitored internally by a Steering group to ensure also the constant flow of information and assay data, and distribution of protocols and of samples/reagents.