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的重叠区域，这增加了人畜共患病病原体的传播风险。其中包括有牲畜市场和后院的城市地区，以及果蝠的城市繁殖地和栖息地，果蝠被猎杀并作为肉食出售。由于市政基础设施差和居民缺乏卫生知识，这些风险更大。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。在第一步中，使用一种健康方法，将确定小反刍动物（RVFV）和猪（HNLV）的血清阳性率，以揭示虫媒病毒和蝙蝠相关感染的潜在热点。喀麦隆的RVFV发病率数据已经有了，而尼日利亚的RVFV情况和HNLV感染的存在还有待确定。在潜在的高感染风险地区，将采集上述物种的样本，并使用分子诊断和血清学方法进行检测，以揭示持续性或克服布尼亚病毒和副粘病毒感染。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种属（通过问卷调查确定）接触的人类样本。在拟定项目的第二部分中，将在体外用RVFV分离株感染源自上述潜在储库宿主的细胞系，并使用HNLV转录和复制能力病毒样颗粒（trVLP）获得这些种属敏感性的证据。弗里德里希-吕弗勒研究所（FLI）可提供蝙蝠（埃及长尾蝠、非洲长尾蝠）以及各种啮齿动物和其他物种（如灰腹鼠、黑线姬鼠、褐家鼠）的细胞系，合作伙伴（波恩的Drosten教授、慕尼黑的Drostenbauer博士）可提供更多的果蝠和啮齿动物细胞系。将用RVFV对果蝠（Rousettus aegyptiacus）、大鼠（Rattus rattus）和田鼠以及青蛙（Xenopus laevis）进行体内攻击研究，以确定这些物种的易感性、发病机制、感染过程和病毒脱落。这项工作将在森林研究所和七个非洲伙伴（包括五所大学）的密切合作下进行，其中包括利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，以及非洲博士生在森林研究所进行两次为期六个月的研究访问。将由一个指导小组在内部稳步监测进展情况，以确保信息和测定数据的持续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.