HYDROLOGICAL STUDIES OF SCHISTOSOMIASIS TRANSPORT IN SICHUAN PROVINCE, CHINA

Schistosomiasis is a water-bourne parasitic disease endemic to Sichuan Province of China. Long-term studies of infection and disease ecology in catchments in Sichuan have been supplemented by detailed hydrometr ic measurements to produce a model of water velocity and flow in an ir rigation system. The model provides a means of estimating travel times of two infectious stages of the parasite from source sites to water c ontact exposure sites for individuals of both the human population and the intermediate vector snail populations. The hydrological transport model will be part of an overall model of schistosomiasis transmissio n in the catchments. A GIS system is used to manage spatial data of th e drainage network, land use, infection sources and population centres . The development of the Three Gorges Dam in China will increase marsh lands and irrigation in areas currently free of schistosomiasis. The p otential for the spread of schistosomiasis into these new areas is a m ajor concern. Hydrological models can be of particular importance in a ssessing future environmental risk. (C) 1998 Elsevier Science B.V.