Landscape dynamics and risk modeling of human alveolar echinococcosis
Résumé
Human alveolar echinococcosis (AE) is a rare but fatal liver disease caused by a parasitic tapeworm. Between 1994 and 1997 a medical survey in a rural area in central China revealed the highest incidence rate of the disease recorded in the world to date, with 15.8 percent of the population infected in one village, Hypotheses on the nature of the transmission mechanisms from the natural to human environment focused on the effects of recent landscape change from forest to agricultural land, Archived Landsat MSS and TM data were used to examine relationships between landscape and human AE prevalence in 31 villages. The results showed a significant positive correlation between AE and the proximity of villages to forest, grassland, and shrubland vegetation, and a negative correlation with the area of cultivated land. A predictive model, based on spatial characteristics of the landscape, is now being developed with the aim of designing management tools for disease control.