SARS沿交通线的“飞点”传播模型

Fly Dots" Spreading Model of SARS along Transportation

20 0 3年春SARS在中国部分地区暴发与蔓延 ,情况非常危急。全国集中力量对SARS病原学、实验室诊断和临床治疗以及传播模型、应急反应系统等展开研究。综观此次SARS的传播 ,除有以往流行性疾病传播的一些共同特点外 ,还有一个很明显的特点 :远距离跳跃式传播。这是以往以及目前针对SARS建立的点源扩散模型无法单独解决的。因此提出建立沿交通线的“飞点”传播模型 ,以交通工具为一尺度 ,建立相对封闭的交通工具内的SARS传播模型 ,另以此为基础 ,建立沿交通线这一尺度上的有人员流动的空间传播模型 ,建立二尺度的“飞点”传播模型 ,模拟交通工具内SARS传播的主要影响因子 ,SARS疫区对非疫区疫情的影响效果 ,为SARS防治提供决策支持。

In the beginning of this year,SARS(Severe Acute Respiratory Syndrome)broke out and spread in mainland of China,Hong Kong,Taiwan and other countries,regions successively. The world,especially China,pays high attentions on this public hygiene safety affair and takes various measures to prevent and control the further spreading of SARS.This work began in early April in this background.At this time,the SARS began to spread to Beijing and northern regions of China, but the situation in southern regions,such as Guangdong and Hong Kong is relative stable. The data about SARS spreading,special cases and sources in these regions are available.Through these information,we found the spreading characteristic of SARS has a distinct one besides other common ones,namely,jumped sperad between two points in long distance.This characteristic can not be singly described by the diffusion models for point sources. Pointed to this, a 'fly dots'spreading model along transportation is put forward in this paper,which takes the vehicle as a scale and sets up SARS spreading model in the relative sealed vehicle. Based on this model,in a scale of the transportation, the spatial spreading of SARS due to flow of passengers is modeled. We simulatde the danger probability of SARS sperading, three cases reported in internet,and the affect of Beijing SARS epidemic situation to in Hebei province due to flow of passengers.The results show that this model meets the spacial spreading characteristic of SARS. Not only the vent,and disinfect and others measures affect SARS spreading in vehicle,but time is also an important factor to be considered. The SARS spread along transportation is affected by these regions' population distribution,the SARS epidemic situation in the beginner affect the situation in the regions of the stops in a great degree. The results simulated by the models can be used to support the decision-making