诺如病毒感染的传播动力学研究

Study on epidemic dynamics of norovirus infection

目的利用数学模型分析诺如病毒感染扩散的流行病学规律。方法以仓室模型为基础建立诺如病毒传播动力学模型,依据实际案例用最小二乘法拟合模型参数,用两个配对样本T检验来检验模型的拟合效果。结果人群初始易感性为88%,通过不洁食物致病的概率为1.19%,病人和无症状感染者将疾病传播给他人的概率为17%,潜伏期感染者转变为病人的概率为11%,转变为无症状感染者的概率为89%。无症状感染者对疾病传播的贡献率为91.38%,病人的传播贡献率为7.95%,不洁食物的传播贡献率为0.66%,无症状感染者在诺如病毒传播过程中起到了重要作用。结论模型较好地拟合了诺如病毒感染的整个过程,通过模型有助于解释诺如病毒感染的流行病学规律。

Objective To analyze the epidemiology mechanism of the epidemic propagation of norovirus infection by mathematical model analysis. Methods An epidemic propagation model of norovirus was constructed based on the compartmental model, in which the parameters were fitted according to an actual case using the least squares fitting method, and the fitness of the model was tested by two paired sample T test. Results The initial susceptibility of the group is 88%. The probability of getting infected by contaminated food is 1.19%, and by patients and asymptomatic infections is 17%. The probability of incubatory carrier turns into patient is 11%, and the other 89%will turn into asymptomatic infections. The contribution rate of asymptomatic infections to disease propagation is 91.37%,7.97% for patients and 0.66% for contaminated food. Asymptomatic infections play an important role in the propagation of norovirus. Conclusion The model can fit the process of norovirus infection preferably and it ＇s helpful to explain the epidemiology mechanism of norovirus infection.