Remote sensing for disease transmission: small mammal and vegetation interactions

Remote sensing, in conjunction with a GIS approach, is used in this research to define landscape structure from classified Landsat-7 ETM+ imagery of a Tibetan study area. A number of distinct landscape cover classes are contained within a site in Serxu county, Sichuan Province, China. Vegetation disturbance is caused primarily by small mammal feeding patterns and yak overgrazing. Cover-specific small mammal numbers have been recorded and landscape ecology techniques are employed to link landscape and rodent data. Initial results show a strong correlation (r/sup 2//spl ap/0.9) between landscape composition and fragmentation, and rodent numbers. Understanding these interactions is important when studying the transmission of Echinococcus multilocularis, the world's most dangerous tapeworm endemic to parts of western China. Infection with the larval stage causes human alveolar echinococcosis, a rare but fatal disease of the liver. If the role of the landscape in the transmission cycle can be defined then methods of control can be suggested. This paper outlines the disease background and concentrates on the rodent-landscape link for the site in Tibet.