Impact of Inter-city Population Mobility and Public Transport Policies on Infectious Epidemics -- Talking about Public Health and Safety from COVID-19

Background: On December 31, 2019, the Wuhan Municipal Health and Health Commission of Hubei Province, China, reported 27 cases of unknown pneumonia. On January 22, Wuhan City implemented the strategy of "closed city" to cut off the communication between Wuhan and the outside areas. Subsequently, there was a nationwide outbreak of infection in China. This article takes the COVID-19 infection as the research object, and uses the mobile phone positioning system to obtain the Wuhan city population migration data from January 1 to February 10, 2020, compares the published data on the number of outbreaks in various cities, and studies the inter-city population relevant models of mobile and epidemic infections, and analyzes the role of policy-oriented epidemic control in the special period of infectious diseases by means of controlling public transportation. Research foundation: Based on Baidu migration big data, we can get the number of people moving in and out of the base city and the source city or target city daily, which gives the data basis for the study. As an important guiding policy for major cities in the world, public transport priority policies have made important contributions to the city's economic development and functional compound. However, during the special period of infectious epidemics, China did not prepare a corresponding emergency plan with public transportation, resulting in no effective measures in the early period; but China accurately makes important decisions to close the outgoing passages of infectious source city, takes certain compulsory measures in the face of risk issues and implements them strictly, and has achieved results in the means of intercity traffic blocking, providing a real case study for this study. Research contents: (1) Using January 1 to February 10, 2020 as the survey time range, using mobile phone positioning big data systems to obtain the top 30 cities and their populations from Wuhan during this period. Combined with the daily epidemic situation of each city announced by the government, this paper analyzed the relevant models of population movement and epidemic infection by GIS, SPSS and other technical methods. (2) After Wuhan “closed city” policy, it cut off the traffic links between Wuhan and other cities. The necessity of "closed city" measures can be seen by comparing the effectiveness of China and other countries in the control of the outbreak. For the special period of the epidemic, this study explores the supplement and improvement of public transport policies through case comparison and effect analysis of this case. Research results: (1) The nationwide infectious epidemic has a strong correlation with the outflow of population in the source city in the early stage. Due to the incubation period of 14 days, the increase in the number of people in other cities is lagging compared to the outflow of population. The parameters include the number of confirmed patients, the incubation period, and indicators of population mobility, etc. (2) The Transit First Policy still has an advantageous role in the special situation of infectious epidemics, but it is necessary to appropriately reduce bus priorities and improve measures and means in public safety, including routes, time, relaxation of private cars, etc. Research value: This article explores the relevant models of inter-city population movement and the spread of infectious epidemics by studying China ’s real epidemic prevention situation, and analyzes the importance of public transportation policies for maintaining urban safety and citizens ’health during special periods with public transportation as an entry point. The proposed policy improvement and emergency plan for public transport in special periods have the universality for large cities when facing major risks.