Emmett Interdisciplinary Program in Environment and Resources, Stanford University, Stanford, California.
Centre de Recherche Biomédicale - Espoir Pour la Santé, Saint Louis, Sénégal.
Am J Trop Med Hyg. 2019 Oct;101(4):837-847. doi: 10.4269/ajtmh.19-0099.
Human schistosomiasis is a snail-borne parasitic disease affecting more than 200 million people worldwide. Direct contact with snail-infested freshwater is the primary route of exposure. Water management infrastructure, including dams and irrigation schemes, expands snail habitat, increasing the risk across the landscape. The Diama Dam, built on the lower basin of the Senegal River to prevent saltwater intrusion and promote year-round agriculture in the drought-prone Sahel, is a paradigmatic case. Since dam completion in 1986, the rural population-whose livelihoods rely mostly on agriculture-has suffered high rates of schistosome infection. The region remains one of the most hyperendemic regions in the world. Because of the convergence between livelihoods and environmental conditions favorable to transmission, schistosomiasis is considered an illustrative case of a disease-driven poverty trap (DDPT). The literature to date on the topic, however, remains largely theoretical. With qualitative data generated from 12 focus groups in four villages, we conducted team-based theme analysis to investigate how perception of schistosomiasis risk and reported preventive behaviors may suggest the presence of a DDPT. Our analysis reveals three key findings: 1) rural villagers understand schistosomiasis risk (i.e., where and when infections occur), 2) accordingly, they adopt some preventive behaviors, but ultimately, 3) exposure persists, because of circumstances characteristic of rural livelihoods. These findings highlight the capacity of local populations to participate actively in schistosomiasis control programs and the limitations of widespread drug treatment campaigns. Interventions that target the environmental reservoir of disease may provide opportunities to reduce exposure while maintaining resource-dependent livelihoods.
人类血吸虫病是一种由蜗牛传播的寄生虫病,影响全球超过 2 亿人。与受蜗牛污染的淡水直接接触是主要的暴露途径。水管理基础设施,包括水坝和灌溉系统,扩大了蜗牛的栖息地,增加了整个景观的风险。迪亚曼大坝建在下塞内加尔河的下游流域,旨在防止海水入侵并促进萨赫勒地区常年农业生产,是一个典型的案例。自 1986 年大坝建成以来,其农村人口(其生计主要依赖农业)的血吸虫感染率居高不下。该地区仍然是世界上血吸虫病高度流行的地区之一。由于生计和有利于传播的环境条件之间的趋同,血吸虫病被认为是一种疾病驱动的贫困陷阱(DDPT)的例证。然而,迄今为止,关于该主题的文献仍然主要是理论性的。我们通过在四个村庄的 12 个焦点小组产生定性数据,进行了基于团队的主题分析,以调查对血吸虫病风险的感知和报告的预防行为如何表明存在 DDPT。我们的分析揭示了三个关键发现:1)农村村民了解血吸虫病风险(即感染发生的地点和时间),2)因此,他们采取了一些预防措施,但最终,3)由于农村生计的特点,暴露仍然存在。这些发现强调了当地居民积极参与血吸虫病控制计划的能力,以及广泛的药物治疗运动的局限性。针对疾病环境储库的干预措施可能提供减少暴露的机会,同时维持资源依赖型生计。