arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2005.04365q-bio.PEcs.NAmath.NAq-bio.QM
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SE(A)IR COVID-19扩散模型参数的贝叶斯动态估计

Bayesian dynamical estimation of the parameters of an SE(A)IR COVID-19 spread model

Daniela Calvetti, Alexander Hoover, Johnie Rose, Erkki Somersalo

摘要:

在本文中,我们考虑了COVID-19感染传播的动态流行病学模型。从经典的SEIR模型出发,对该模型进行了改进,使其更好地描述了潜在病原体及其传染模式的特征。与大量与接触有记录的感染性个体无关的继发感染一致,该模型包括一组无症状或症状轻微的感染性个体,未计入新的每日感染计数数据。贝叶斯粒子滤波算法用于动态更新相关队列,并同时估计传播率,因为新的感染和疾病相关死亡人数的新数据变得可用。该模型的基本假设是,传染率是动态变化的流行病期间,无论是因为病原体的突变或响应缓解和遏制措施。序贯贝叶斯框架自然提供了模型参数估计的不确定性的量化,包括繁殖数量和不同队列的大小。此外,我们引入了一个无量纲的量,这是无症状和有症状的队列规模之间的平衡比,并提出了一个简单的公式来估计的数量。这个比率自然地导致了另一个无量纲量,它起着模型的基本再生数$R_0$的作用。当我们将模型和粒子滤波算法应用于俄亥俄州东北部和密歇根州东南部几个县的COVID-19感染数据时,我们发现建议的繁殖数$R_0$在两个州内具有一致的动态行为,因此证明是缓解措施成功的可靠总结。

英文摘要:

In this article, we consider a dynamic epidemiology model for the spread of the COVID-19 infection. Starting from the classical SEIR model, the model is modified so as to better describe characteristic features of the underlying pathogen and its infectious modes. In line with the large number of secondary infections not related to contact with documented infectious individuals, the model includes a cohort of asymptomatic or oligosymptomatic infectious individuals, not accounted for in the data of new daily counts of infections. A Bayesian particle filtering algorithm is used to update dynamically the relevant cohort and simultaneously estimate the transmission rate as the new data on the number of new infections and disease related death become available. The underlying assumption of the model is that the infectivity rate is dynamically changing during the epidemics, either because of a mutation of the pathogen or in response to mitigation and containment measures. The sequential Bayesian framework naturally provides a quantification of the uncertainty in the estimate of the model parameters, including the reproduction number, and of the size of the different cohorts. Moreover, we introduce a dimensionless quantity, which is the equilibrium ratio between asymptomatic and symptomatic cohort sizes, and propose a simple formula to estimate the quantity. This ratio leads naturally to another dimensionless quantity that plays the role of the basic reproduction number $R_0$ of the model. When we apply the model and particle filter algorithm to COVID-19 infection data from several counties in Northeastern Ohio and Southeastern Michigan we found the proposed reproduction number $R_0$ to have a consistent dynamic behavior within both states, thus proving to be a reliable summary of the success of the mitigation measures.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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