SARS传播数学模型与流行趋势预测研究

目的 为进一步探索SARS的传播和流行规律及其与防治措施的关系，并为此提供数学工具；方法 通过数学和传播动力学的方法，建立数学模型，与广东省和北京市部分实际资料进行拟合和模拟预测；结果 建立了适用于SARS模拟和预测的确定性微分方程模型，提出了SARS传播阈值的概念和计算公式，在传播速率，传播阈值与两地流行过程及其与防治措施之间的关系上取得了较好的拟合；结论 预测广东省和北京市SARS的流行将于6月上旬或中旬基本结束，这是由于防治措施已使传播速率和基本繁殖率下降至临界值以下的必然结果，提示在保持一定的控制措施和使传播速率降至一定水平的情况下，SARS的流行是可以防止和控制的。

Mathematical model and prediction of epidemic trend of SARS

Objective To further search the rule of SARS transmission and epidemic and its relation with public health interventions, and to provide a mathematical model for it; Methods To build a mathematical model by mathematics and transmission dynamics way and to fit with the partial data of SARS incidence in Guangdong Province and Bejing City; Results Deterministic differential equations have been builded which is able to use for SARS. A better fitting in relation among the transmission velocity, the transmission threshold, the course of epidemics in both Guangdong and Beijing and the public health interventions was obtianed; Conclusion It was predicted that the epidemics in both Guangdong and Bejing will be ended by the first 10 days or the second 10 days of June because the transmission velocity and the basic reproduction rate of SARS have been declined to below the critical level by the control measures implemented. And it is suggested that the epidemics of SARS is able to prevent and control under keeping enough public health interventions which lead to lower the basic reproduction rate of SARS.