应用SEIR模型预测2009年甲型H1N1流感流行趋势

Prediction of the epidemic trends of pandemic H1N1 2009, using SEIR model

目的探讨SEIR模型预测甲型H1N1流感流行趋势的功效。方法利用国庆前北京市流感样病例数、流感样病例中甲型H1N1流感阳性率及二级以上医院流感样病例就诊率等参数估算甲型H1N1流感实际感染人数，基于传染病传播动力学，建立SEIR模型，对国庆后甲型H1N1流感的流行趋势及高峰达到时间进行预测，与甲型H1N1流感病原学监测结果进行比较，评价模型的预测效果。结果经SEIR模型估算，2009年北京市甲型H1N1流感的平均潜伏期约为1．51天，平均感染期为2．12天，基本再生数为1．28。病原学监测结果显示：2009年甲型H1N1流感于11月初达到高峰，而SEIR模型预测2009年甲型H1N1流感最晚将于12月4日达到高峰。结论SEIR模型可根据流感流行的初期监测数据预测其未来流行趋势。

Objective To explore the efficiency of SEIR model （susceptible, exposed, infectious and recovered model） for predicting the trend of pandemic H1N1 2008. Methods Data of the number of influenza-like illness cases（ ILIs）, pandemic influenza A （H1N1 ） 2009 positive rate among ILls and rate on clinical visit of ILIs before National Day （ October 1 ） were collected and analyzed to develop SEIR model for predicting the trend of pandemic H1N1 2009 after National Day, based on dynamics of infectious disease transmission. The results were compared with the results from and pandemic H1N1 2009 virologic surveil- lance data to evaluate the efficiency of SEIR model. Results The mean incubation period of pandemic H1N1 2009 was estimated 1.51 days, with a mean duration of infectiousness of 2. 12 days, and a mean basic reproductive number of 1.28. As shown in the virologic surveillance data, pandemic H1N1 2009 peaked in early November. However, SEIR model predicted that pandemic H1 N1 2009 would peak no later than December 4th. Conclusion SEIR model could be developed to predict the trend of pandemic influenza based on the early surveillance data.