Transmission ecology and risk factors for cystic echinococcosis in sub-Saharan Africa

撒哈拉以南非洲是受人类和牲畜囊性包虫病（CE）影响最严重的地区之一。经过几十年的忽视，近年来人们对引起CE的各种棘球蚴的地理分布和宿主物种的参与有了相当多的了解。撒哈拉以南非洲逐渐成为世界上病原体最多样化和传播模式最复杂的区域。尽管取得了这一进展，但在特定地区决定各种疾病因子存在和频率的因素仍然知之甚少。这与人类健康有关，因为不同棘球绦虫对人类疾病负担的贡献不同，其中对全球和非洲公共卫生影响最大的是严格的细粒棘球绦虫。因此，重要的是了解决定这些寄生虫在不同空间尺度上传播的因素，并最终建立CE的预测情景（通常影响难以进入的偏远地区）。我们建议在联盟成员已经确定棘球绦虫存在和大致丰度等基本参数的选定地区进行传播生态学研究。这些地区在疾病影响程度、宿主动物物种的存在、环境参数和经济条件方面变化很大，被选为具有较大区域代表性的地区。在埃塞俄比亚、肯尼亚、赞比亚、纳米比亚和加纳的七个地区，除了有关人类活动的数据外，还将建立关于不同棘球蚴种类和基因型引起的人类、牲畜和野生动物CE的定量数据。这将用于制定大规模的预测模型，并选择预测变量，如土地覆盖、气候、牧区传统、狗的管理以及野生和国内收容社区。此外，这些数据将用于生成对不同国家人类健康和经济影响的精确数字。此外，将与尚未缺乏棘球绦虫存在/不存在数据的国家（例如西非和中非）的医疗和兽医机构建立联系，并将进行探索性实地调查。该项目将通过提供流行病学、分子生物学、超声波、野生动物生态学和相关学科的专门培训，加强联盟成员的研究能力。重点将放在把现有的实验室升级到具有竞争力的标准，以及建立非洲内部的科学交流，而不是依赖欧洲的专门知识。为了确认研究的科学质量，传播生态学、流行病学、经济评估和临床诊断方面的国际知名专家已同意担任非洲财团成员的外部顾问和进一步的合作伙伴。

Sub-Saharan Africa is one of the regions most seriously affected by cystic echinococcosis (CE) of humans and livestock. After decades of neglect, considerable knowledge has been gained in recent years on geographical distribution and host species involvement of the various Echinococcus species that cause CE. Sub-Saharan Africa gradually emerges as the world region with the highest diversity of causative agents and with the highest complexity of transmission patterns. Despite this progress, factors that determine presence and frequency of the various disease agents in particular areas remain little understood. This is relevant for human health, as different Echinococcus spp. contribute unequally to human disease burden with E. granulosus sensu stricto having the highest impact on public health both globally and in Africa. It is therefore important to understand the factors that determine the transmission of these parasite at different spatial scales and eventually to establish predictive scenarios for CE (that often affects remote areas that are difficult to access). We propose studies in transmission ecology in selected areas where basic parameters such as presence and approximate abundance of Echinococcus spp. have already been identified by consortium members. Selected to be representative for larger regions, these areas are highly variable concerning levels of disease impact, presence of host animal species, environmental parameters and economic conditions. In each of seven areas in Ethiopia, Kenya, Zambia, Namibia and Ghana, quantitative data on human, livestock and wildlife CE caused by different Echinococcus species and genotypes will be established in addition to data on relevant human activities. This will be used to formulate large scale predictive models and select predictive variables such as land cover, climate, pastoral traditions, dog management, and wild and domestic host communities. In addition, the data will be used to generate precise figures on the impact on human health and the economy in different countries.In addition, contacts to medical and veterinary institutions will be established in countries that are yet data deficient concerning presence / absence of Echinococcus spp. (e.g. western and central Africa) and explorative field surveys will be done.The project will strengthen the research capacities of the consortium members by offers for specialized training in epidemiology, molecular biology, ultrasonography, wildlife ecology and related subjects. Emphasis will be placed to upgrade existing laboratories to competitive standards, and to establish a within-Africa scientific exchange rather than reliance on European expertise. To confirm the scientific quality of the research, internationally renowned experts for transmission ecology, epidemiology, economic assessments and clinical diagnostics have agreed to serve as external consultants and further cooperative partners for the African consortium members.