Soil-transmitted helminthiases in China: a spatial statistical analysis.

The prevalence of the soil-transmitted helminthiases is extremely high in some rural areas in China. The endemic foci of these human parasites constitute one of the most neglected public health problems. A large scale survey on human parasites (1988-1992) was conducted in China. The prevalences of the soil-transmitted helminthiases in the 30 provinces, autonomous regions and municipalities were reported and correlated with ecological factors (Yu et al, 1994; Xu et al, 1995). In this paper, we re-examined and analyzed the reported results with a spatial pattern test statistic, the D statistic. The values of the D statistic indicated that the spatial correlation of the prevalence of the soil-transmitted helminthiases in China was significant. We also found that the spatial correlation of the prevalence could largely be explained by the paddy field area per capita. The correlation of the prevalence of the soil-transmitted helminthiases and the paddy field area per capita was higher than the correlation of the prevalence with the factors found previously by Xu et al (1995).