Schistosomiasis (bilharzia) is a neglected tropical disease caused by trematode worms of the genus Schistosoma. The transmission cycle involves human (or other mammalian) water contact with surface water contaminated by faeces or urine, as well as specific freshwater snails acting as intermediate hosts. The main disease-causing species are S. haematobium, S. mansoni and S. japonicum. According to the World Health Organisation, over 250 million people are infected worldwide, leading to considerable morbidity and the estimated loss of 1.9 million disability-adjusted life years (DALYs), a likely underestimated figure. Schistosomiasis is characterised by focal epidemiology and an over-dispersed population distribution, with higher infection rates in children. Complex immune mechanisms lead to the slow acquisition of immune resistance, but innate factors also play a part. Acute schistosomiasis, a feverish syndrome, is most evident in travellers following a primary infection. Chronic schistosomiasis affects mainly individuals with long-standing infections residing in poor rural areas. Immunopathological reactions against schistosome eggs trapped in host tissues lead to inflammatory and obstructive disease in the urinary system (S. haematobium) or intestinal disease, hepatosplenic inflammation and liver fibrosis (S. mansoni and S. japonicum). An effective drug—praziquantel—is available for treatment but, despite intensive efforts, no schistosomiasis vaccines have yet been accepted for public use. In this review, we briefly introduce the schistosome parasites and the immunopathogenic manifestations resulting from schistosomiasis. We then explore aspects of the immunology and host-parasite interplay in schistosome infections paying special attention to the current status of schistosomiasis vaccine development highlighting the advancement of a new controlled human challenge infection model for testing schistosomiasis vaccines.

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血吸虫病——从免疫病理学到疫苗。

血吸虫病 (bilharzia) 是一种被忽视的热带疾病，由血吸虫属的吸虫引起。传播周期涉及人类（或其他哺乳动物）水与被粪便或尿液污染的地表水以及充当中间宿主的特定淡水蜗牛接触。主要致病菌为血吸虫、曼氏吸虫和日本吸虫. 根据世界卫生组织的数据，全世界有超过 2.5 亿人受到感染，导致发病率很高，估计损失了 190 万残疾调整生命年 (DALY)，这个数字可能被低估了。血吸虫病的特点是局部流行病学和人口分布过于分散，儿童感染率较高。复杂的免疫机制导致免疫抵抗的缓慢获得，但先天因素也起作用。急性血吸虫病是一种发热综合征，在初次感染后的旅行者中最为明显。慢性血吸虫病主要影响居住在贫困农村地区的长期感染者。针对滞留在宿主组织中的血吸虫卵的免疫病理学反应导致泌尿系统炎症和阻塞性疾病。S. haematobium）或肠道疾病、肝脾炎症和肝纤维化（S. mansoni和S. japonicum）。一种有效的药物 - 吡喹酮 - 可用于治疗，但尽管付出了巨大努力，但尚未接受任何血吸虫病疫苗供公众使用。在这篇综述中，我们简要介绍了血吸虫寄生虫和血吸虫病引起的免疫致病表现。然后，我们探讨了血吸虫感染中免疫学和宿主-寄生虫相互作用的各个方面，特别关注了血吸虫病疫苗开发的现状，突出了用于测试血吸虫病疫苗的新受控人类挑战感染模型的进步。