基于SEIR模型的COVID-19疫情防控效果评估和预测

通过对COVID-19疫情在中国的传播情况进行分析，建立了一个SEIR流行病模型，模型中将确诊人群分成已收治和未收治两类.先从理论上分析了模型的无病平衡点及其稳定性、基本再生数等关键问题；再结合实际数据，对武汉封城前和封城后两个阶段疫情的发展趋势进行数值模拟和比较分析，讨论了模型中一些重要参数对确诊人数的影响；最后，针对上述理论分析和数值模拟的结果，对之前采取的一些控制策略作了分析评估，同时对疫情后期发展进行预测.

Evaluation and Prediction of Prevention and Control Effects of the COVID-19 Epidemic Based on the SEIR Model

Based on the analysis of the spread of the COVID-19 epidemic in China, a SEIR epidemic model was established with the diagnosed population divided into 2 categories: the admitted population and the non-admitted population. Through theoretical analysis, the basic reproduction number, the disease-free equilibrium of the model and its stability were derived. Further, several numerical simulations and comparative analysis were conducted on the development trend of the epidemic situation in Wuhan before and after the city closure, as well as the influences of some important parameters in the model on the number of diagnosed cases. Finally, according to the results of above theoretical analysis and numerical simulations, some control strategies previously adopted were analyzed and evaluated, and predictions were made for the development of the epidemic.