Developing a locally viable water filtration method to provide safe drinking & bathing water from Lake Victoria in a Schistosoma mansoni endemic area.

战略重点领域：水利工程。设计/优化与水资源管理、处理和分配系统（包括废水和污水）有关的技术。血吸虫病是一种被忽视的热带病，感染人数超过2.4亿，主要在撒哈拉以南非洲，每年造成约20万人死亡，数百万儿童和成人患重病。传播与贫穷有着内在联系，贫穷是由水、环境卫生和个人卫生条件差造成的。个人在接触含有尾蚴的淡水时会受到感染，尾蚴是寄生虫的感染性幼虫阶段，在接触后直接穿过皮肤。与水的接触是通过取水和洗澡等行为发生的。在卫生条件不充分的地区，水污染和通过水接触传播疾病的情况很高，寄生虫卵随人类尿液和粪便排出。目前，大规模给药是主要的控制形式，但需要改进讲卫生设施，以阻断传播和减少再感染。生物过滤和慢砂过滤器是简单的，成本效益高的生物技术，可用于饮用水净化。在生物过滤器内形成的复杂生物膜分解营养物质和/或消除病原体（如病毒和细菌病原体），使水安全饮用。然而，生物学通常没有完全理解，因此没有完全优化效率或有针对性地去除特定病原体和/或污染物。例如，预计缓慢的沙过滤器也可以从水中去除血吸虫幼虫等寄生虫。然而，这些技术尚未在血吸虫病流行地区进行充分优化和测试，以处理水以减少血吸虫病传播和一系列其他水传播污染物。本博士课程将探讨低成本水过滤系统的设计、有效性和吸收问题，该系统通过使用低成本、低能耗的生物过滤器提取和处理湖水，使其安全用于饮用、沐浴和其他家庭用途。该项目将包括1)在英国的实验室工作，设计、测试和优化使用实验室生命周期中的尾蚴的过滤方法。在乌干达的实地工作将侧重于2)为未来的当地生产确定合适的、当地可获得的材料，提高未来干预措施的可持续性，以及3)对来自流行地区的家庭进行寄生虫学和流行病学研究，以评估有和没有处理过的水的家庭的过滤使用情况和再感染水平。总体目标是开发一种生物过滤系统，通过优化生物学来去除血吸虫和其他水生污染物，这些污染物可以在流行社区内后勤和经济地制造，以有效地处理感染性湖水，使其安全用于饮用、洗澡和家庭使用。具体目标包括：1：优化慢沙生物过滤器在实验室中去除和/或灭活血吸虫尾蚴的功效；2：在社区进行定性调查，以确定对水过滤设计和位置的偏好；2：确定未来使用当地采购的材料和劳动力制造低成本过滤器的材料和技能。3：监测乌干达流行社区中使用新过滤系统的家庭和没有额外干预措施的家庭的过滤使用情况和曼氏血吸虫感染和再感染水平。将获得环境工程和微生物学、寄生虫学、现场流行病学方面的技能，并通过我们在乌干达病毒研究所的合作者了解社会科学、卫生经济学和当地制造业。

strategic priority area:Water engineering. Design/optimisation of technologies relating to water resource management, treatment and distribution systems (including waste water and sewerage).Keywords:WASH, filtration, disease, sustainable, schistosomiasisSchistosomiasis is a neglected tropical disease infecting over 240 million people, mainly in sub-Saharan Africa, causing approximately 200,000 deaths a year and severe illness in millions of children and adults. Transmission is intrinsically linked to poverty, driven by poor water, sanitation and hygiene (WASH) conditions. Individuals acquire infections when they contact fresh water containing cercariae, the infective larval stage of the parasite, which burrow directly through the skin upon contact. Water contact occurs through behaviours such as water collection and bathing. Water contamination, and hence disease transmission through water contact, is high in areas with inadequate sanitation with the parasite eggs excreted in human urine and stool. Presently, mass drug administration is the main form of control, but improved WASH facilities are required to interrupt transmission and reduce reinfection. Biofiltration and slow sand filters are simple, cost effective biotechnologies available for drinking water purification. The complex biofilms that form within the biofilters breakdown nutrients and/or eliminate pathogens (such as viral and bacterial pathogens) to make the water safe for drinking. However, the biology is often not fully understood and therefore not fully optimised for efficiency or targeted removal of particular pathogens and/or contaminants. For example, slow sand filters would be expected to also remove parasites such as Schistosoma larval stages from the water. However, these technologies have yet to fully optimised and tested in Schistosoma endemic areas for the treatment of water to reduce schistosomiasis transmission and a range of other water borne contaminants. This PhD will address questions surrounding the design, effectiveness, and uptake of a low-cost water filtration system to extract and treat lake water by passage using low cost, low energy biofilters to make it safe for drinking, bathing and other domestic uses. The project will involve 1) working in the laboratory in the UK to design, test and optimise the filtration methods using cercariae from laboratory life cycles. Field work in Uganda will focus on 2) identifying suitable, locally available materials for future local manufacturing, enhancing sustainability of future interventions, as well as 3) performing parasitological and epidemiological studies with households from endemic areas to assess filtration usage and reinfection levels in families with and without access to treated water.The overarching aim is to develop a biofiltration system, by optimising the biology to remove Schistosoma and other water borne contaminants, that can logistically and affordably manufactured within endemic communities, to efficiently treat infectious lake water to make it safe for drinking, bathing and domestic use. Specific objectives include:1: Optimising the efficacy of slow-sand biofilters for the removing and/or inactivating schistosome cercariae in the laboratory2: Performing qualitative surveys in communities to identify preferences for water filtration design and location2: Identify materials and skills for the future manufacturing of low-cost filters using locally sourced materials and labour.3: Monitor filtration usage and Schistosoma mansoni infection and reinfection levels in families in endemic communities in Uganda with access to the new filtration systems and those with no additional interventions.Skills will be gained in environmental engineering and microbiology, parasitology, field epidemiology and with an understanding in social sciences, health economics and local manufacturing gained through our collaborators at the Ugandan Virus Research Institute.