The study of human behavior and schistosomiasis transmission in an irrigated area in Morocco
Introduction
Next to malaria, schistosomiasis has in recent times been one of the most destructive diseases in tropical and subtropical areas. It weakens and debilitates the sufferer, affects people's ability to carry out physical labor and, if untreated, in the long term undermines the functioning of the liver and ultimately causes death (Farley, 1991). Irrigation and other water development projects present particularly favorable locales for the survival and spread of the disease. The possibility of extremely high rates of infection in newly irrigated areas, or those in which irrigation is being expanded, is demonstrated in the Richard Toll irrigation project near the mouth of the Senegal River. Here, a recent outbreak of Schistosoma mansoni in one village recorded an infection rate of almost 100% in people over 5 years of age (Stelma et al., 1993). Schistosomiasis is not a disease threat to be taken lightly.
The transmission of schistosomiasis occurs when humans come into contact with water containing schistosomes which penetrate the skin, following the contamination of the water by infected humans who excrete schistosome eggs in feces (in the case of Schistosoma mansoni) or in urine (in the case of S. haematobium). To complete their life cycle, and infect humans, the schistosome requires an intermediate snail host in the water source. The disease persists because people in endemic areas continue to contaminate water during excretory activities, and come into contact with potentially infective water sources during domestic, recreational and agricultural activities.
An understanding of who, where, how, when and why people engage in behavior which puts them at risk of perpetuating or contracting schistosomiasis through water contact activities should be essential input in any integrated schistosomiasis control programs. Answering these questions requires collaboration between researchers in the social sciences and those in the fields of medicine, biology, parasitology and engineering. Planning and implementation should also involve the staff in various government sectors, including health, irrigation, agriculture, and potable water supply. However, there is frequently a lack of communication among these groups because of different professional and sectoral interests (Hunter et al., 1993).
This paper presents a strategy for studying water use and water contact which has been devised for use in an interdisciplinary research project in the Tessaout Amont irrigation scheme in the Haouz plain of central Morocco. This setting, with many scattered water contact sites, many activities carried out at these sites, and the small number of people involved, was not appropriate for a conventional water contact study based on the observation of water contact sites, such as the author and her Egyptian colleagues had carried out in the Nile delta.
The strategy developed in the Moroccan setting utilizes three related concepts: the household, time geography, and the gendered use of space. Preliminary findings of the on-going project are presented. The setting for this study is briefly contrasted with that of the Nile delta villages in which an observational study was conducted. The suitability of the strategy in other settings is briefly explored.
Section snippets
The study of water contact
Epidemiologists and geographers have carried out water contact observations to identify exposure behavior in order to identify "risk factors" for schistosomiasis infection. These observational studies have been found to be more reliable than interview schedules because they identify what people actually do, rather than what they say they do. Farooq pioneered water contact observations in four villages in the Nile delta in the early 1960s (Farooq et al., 1966). In 1978/79, the geographer Helmut
The research project
The strategy discussed in this paper has been developed during a social science project, funded by WHO/TDR and operating in collaboration with a larger European Union/Avicenne study involving malacologists, epidemiolgists, physicians, parasitologists and engineers who are investigating the feasibility of environmental interventions to control the transmission of schistosomiasis in the Tessaout Amont irrigation scheme. The TDR social scientists are studying water use and water contact behavior
Understanding water use and water contact patterns
The preliminary findings reveal the complexity and variability in water collection and water use in space and time, and the possibility of water contact. Within each household water related activities can be understood in terms of the complex interrelationship between household resources and composition, and the availability and accessibility of water for various tasks. Choices of which water sources to use are made within the context of water scarcity and the changing patterns of water
Acknowledgements
This investigation received financial support from the UNDP/World Bank/WHO Special Programme for research and Training in Tropical Diseases (TDR), #940880. Thanks are due to all members of the EU/Avicenne team in Morocco and Leiden, and colleagues in Egypt. We are also grateful for the cooperation and hospitality of the people of Tessaout Amont. Thanks also to Anders Schaerstrom for a stimulating discussion of time geography during the Portsmouth symposium. Eline Boelee, of the University of
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