Department of Basic Medicine, Xianning College, Xianing, Hubei 437100, PR China.
Acta Trop. 2010 Jul-Aug;115(1-2):119-25. doi: 10.1016/j.actatropica.2010.02.012. Epub 2010 Feb 25.
Hubei Province, along with four other provinces in the central and eastern China where schistosomiasis is endemic (Anhui, Hunan, Jiangsu, and Jiangxi), is located in the lake and marshland regions along the Yangtze River. High population density, large numbers of farm cattle, and huge areas of snail habitat are the main characteristics that maintain the persistence of the disease and the transmission of the parasite Schistosoma japonicum in these regions. Based on the schistosomiasis infection data from Hubei province, we propose a mathematical model for the human-cattle-snail transmission of schistosomiasis. The model is a system consisting of six ordinary differential equations that describe susceptible and infected human, cattle and snail subpopulations. After analyzing the existence of the disease-free equilibrium of the model, we determine the basic reproduction number and use the model to simulate the schistosomiasis infection data from Hubei Province. By carrying out sensitivity analyses of the basic reproduction number on various parameters, we find that the transmission of S. japonicum between cattle and snails plays a more important role than that between humans and snails in the endemicity of schistosomiasis in these regions. This strongly suggests that, to control and eventually eradicate schistosomiasis in the lake and marshland regions in China, a more comprehensive approach needs to include environmental factors in order to break the cattle-snail transmission cycle.
湖北省与中国东部和中部的其他四个血吸虫病流行省份（安徽、湖南、江苏和江西）一样，位于长江沿岸的湖泊和沼泽地区。高人口密度、大量的耕牛和大面积的钉螺栖息地是这些地区维持血吸虫病持续存在和寄生虫日本血吸虫传播的主要特征。根据湖北省血吸虫病感染数据，我们提出了一个人类-牛-螺传播血吸虫病的数学模型。该模型是一个由六个常微分方程组成的系统，描述了易感人群和感染人群、牛和螺亚群。在分析模型无病平衡点的存在性之后，我们确定了基本再生数，并使用模型模拟了湖北省的血吸虫病感染数据。通过对各种参数的基本再生数进行敏感性分析，我们发现牛螺之间日本血吸虫的传播在这些地区的血吸虫病流行中比人螺之间的传播更为重要。这强烈表明，为了控制和最终消除中国湖区和沼泽地区的血吸虫病，需要采取更全面的方法，包括环境因素，以打破牛螺传播周期。
