基于泊松过程的山东省新型冠状病毒肺炎的再生数估计及流行动态分析

目的 探讨山东省新型冠状病毒肺炎(COVID-19)的流行动态,为未来预防和控制COVID-19二次暴发以及其他新发传染病的暴发提供科学依据。 方法 收集山东省卫生健康委员会报告的559例COVID-19确诊病例信息,确定病例的感染日期,基于泊松过程建立传播模型并计算山东省COVID-19疫情期间的基本再生数和瞬时再生数,并对比分析基于顺序贝叶斯和时间-依赖方法的瞬时再生数估计结果。 结果 确诊病例的发病日期与被报告日期的天数之差大致服从威布尔分布。山东省COVID-19开始暴发时,基本再生数R0=2.64(95%CI:1.37~4.51),瞬时再生数随着时间的推移,大致呈现逐渐下降趋势,且3种计算方法的结果均显示出此种趋势。 结论 经过防控措施的干预后,山东省COVID-19的本地流行已经基本结束,但仍需提高警惕,防止疫情二次暴发。

Reproduction number estimation and epidemic analysis of coronavirus disease 2019 in Shandong Province based on Poisson process

Objective To explore the epidemic dynamics of coronavirus disease 2019(COVID-19)in Shandong Province, and to provide a scientific basis for the future prevention and control of new outbreaks of COVID-19 and other emerging infectious diseases. Methods After collecting the information of 559 confirmed cases with COVID-19 reported by the Shandong Provincial Health Commission and determining the infection date of the cases, a propagation model was established based on the Poisson process and the basic reproduction number and instantaneous reproduction number were calculated during the COVID-19 epidemic in Shandong Province. The results obtained by calculating the instantaneous reproduction numbers based on sequential Bayesian and time-dependent methods were compared. Results The difference between the date of onset of a confirmed case and the date when it was reported generally followed the Weibull distribution. When the COVID-19 outbreak started in Shandong Province, the basic reproduction number(R₀)was 2.64(95%CI:1.37-4.51), and the instantaneous reproduction number showed a gradually downward trend with time. Three calculation methods all showed the same trend. Conclusion After the intervention of prevention and control measures, the local epidemic of COVID-19 in Shandong Province has basically ended, but the constant vigilance is necessary in order to prevent the second outbreak of the epidemic.