基于交通管控效应的中国COVID-19疫情扩散的时空特征及其危险性

The Spatiotemporal Characteristics and Risks of COVID-19 Pandemic Based on the Effects of Traffic Control

基于中国各级卫健委公布的疫情数据和全国列车数据,结合交通管控措施解析了中国COVID-19疫情扩散的时空特征和危害性,以及湖北“封省”对全国铁路系统的影响,结果发现:1)中国的疫情增长过程高度符合Logistic分布;空间上由湖北往东、南方向蔓延强度较大,各省内部疫情较为严重的地区通常为省会或经济发达城市。基于交通管控对疫情扩散的扰动,揭示了COVID-19的平均潜伏期约为4 d;并基于此测算了疫情的基本再生指数(R0),结果显示:R0整体上呈波动下降趋势,截至2020-04-08全国各地区的R0均趋于1;湖北以外的愈亡比远高于湖北,表明在医疗资源充足的情况下,疫情的危险性可以大幅降低。2)通过湖北“封省”管控前后的铁路网络对比得出,湖北“封省”措施对中心性较高的城市影响较大,尤其是长三角地区,对中心性较低的城市影响微弱;此外,“封省”措施对全国铁路网络整体连通性不会产生根本性的影响。

On December 31st,2019,the Wuhan Municipal Health Commission issued the first report of the pneumonia epidemic of novel coronavirus infection(COVID-19).Studies regarding the relationships between traffic and the epidemic situation are far from systematic.When the epidemic broke out in Wuhan,Hubei province,an important transportation hub of China,it occurred at the peak of Spring Festival-related travel.Therefore,the relationships between the spread of the epidemic and the impact of traffic have remained underexplored.This paper systematically analyzes the spatiotemporal characteristics,hazards,and the growth trend of COVID-19 spread from a macroscopic and full sample perspective,to provide a comprehensive understanding toward epidemic prevention and control in China and abroad.The analysis performed in this article is based on the publicly available data,using the basic reproductive number measure and complex network method.This study found the following.First,the overall growth of the epidemic is exponential,and the outbreak of Hubei province in China has a strong spread in the eastern and southern directions.Provinces such as Jiangsu,Hunan,and Fujian have seen rapid day-to-day growth rates,and the epidemic situation is generally more serious in the capital or the developed city in each province.Based on analyzing the disturbance of the spread of the epidemic through traffic control,the average incubation period of COVID-19 was approximately found to be four days and the number of basic regenerations showed a downward trend in fluctuation.As of April 8th,the R0 in all regions of China tended to be one.The ratio of cure to death outside Hubei province is much higher than that within Hubei province,indicating that with sufficient medical resources,the risk of the epidemic can be greatly reduced,and it is not to be feared.Second,the quarantine policy of Hubei has a greater impact on cities with higher centrality.From the perspective of changes in centrality,most cities in the northern region have increased their centrality,indicating that the region's connection with Hubei Province is relatively weak.The cities with decreasing centrality are mainly located in the Beijing-Guangzhou line and the Yangtze River Delta.Similarly,the changes in the bottom 20 cities on the centrality ranking are also analyzed.Except for a slight change in the ranking,the cities have been not affected.Additionally,before and after the"closing of the Hubei province",the number of edges of China's railway network,Beta and gamma indicators all declined,but the decline was not significant.Thus,although Hubei plays an important role in China's railway network,in general,the"quarantine of the Hubei province"does not have a particularly large impact on China's entire railway network.