Tropical Geography ›› 2020, Vol. 40 ›› Issue (3): 432-445.doi: 10.13284/j.cnki.rddl.003246

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Spatio-Temporal Evolution and Risk Profiling of the COVID-19 Epidemic in Shaanxi Province

Wang Jiaobei1a(), Li Gang1,2(), Wang Jianpo1a, Qiang Jingqi1a, Zhu Dandan1a   

  1. 1.a. College of Urban and Environmental Sciences; b. Institute of Earth Surface System and Hazards, Northwest University, Xi’an 710127, China
    2.Institute of Earth Surface System and Hazards, Northwest University, Xi’an 710127, China
  • Received:2020-04-06 Revised:2020-04-28 Online:2020-05-31 Published:2020-06-30
  • Contact: Li Gang E-mail:849293186@qq.com;lig@nwu.edu.cn

Abstract:

The sudden outbreak and spread of the Corona Virus Disease 2019 (COVID-19) has posed great challenges to the society as well as the academia of not only China but the whole world. The occurrence of epidemic has obvious time and space attributes. Analysis of the spatiotemporal diffusion pattern and process of the epidemic reflects the dynamics of the interaction between humans and the COVID-19, it is worth discussing from the perspective of geography, which is very important for measures for prevention and control of this public health emergency. Based on the confirmed COVID-19 cases’ details manually extracted from the official reports and the relevant Point Of Interest (POI) data, this study aims to reveal the spatiotemporal evolution and risk profiling of the COVID-19 epidemic in Shaanxi province. The results are as follows: Firstly, the age-gender structure of the confirmed cases was diamond-shaped, where more males than females are confirmed, and the overall age trended to be medium-old aged, especially the age group of 40-49. Both non-local and local infections were dominantly caused by the flows of people between cities. Most of the infections belonged to small clusters of core families due to imported cases from Wuhan City, while other large mixed cluster infections in special places may have a deep influence. Secondly, the epidemic evolution process can be roughly divided into three stages, namely wave development stage (Jan.23rd-Feb.6th, 2020), low-speed recession stage (Feb.7th-20th), and stable clearance stage (Feb.21st-Mar.15th). There were lag periods between the cases’ confirmed dates and the onset or initial diagnosis dates. Moreover, the initial reporting dates of confirmed populations were synchronized with the overall evolution of the epidemic. Thirdly, the spatial flow of the epidemic to Shaanxi province was different from that to other provinces around Hubei. That is, it had a unique spatial pattern of only a single cluster center. The overall spatial distribution of the epidemic presented an inverted T-type pattern concentrated in central and southern Shaanxi with significant spatial differentiation. The spatial evolution at the city level was three-pronged. Here, the Wuhan-Xi'an path was the most frequent flow path, exhibiting the flow pattern of "from one source to many sinks, and from Wuhan to central and southern Shaanxi". Finally, the high risk areas were these key cities, for example Xi'an, as shown by the "one big cluster with three small collections" pattern, with the risk level in urban areas being higher than that in the surrounding counties.

Key words: COVID-19, major epidemic, spatio-temporal evolution, risk level, Shaanxi province

CLC Number: 

  • K901