OBJECTIVES: The outbreak of novel coronavirus (COVID-19) epidemic is reaching its final phase in China . The complete epidemic data are available for a complete assessment of epidemiological parameters in all regions and time periods .
METHODS: This study aims to present a spatiotemporal epidemic model based on spatially stratified heterogeneity (SSH) to simulate the epidemic spread . A susceptible-exposed/latent-infected-removed (SEIR) model was constructed for each SSH-identified stratum (each administrative city) to estimate the spatiotemporal epidemiological parameters of the outbreak .
RESULTS: We estimated that the mean latent and removed periods were 5.40 and 2.13 days, respectively . There was an average of 1.72 latent or infected persons per 10,000 Wuhan travelers to elsewhere until January 20th , 2020 . The space-time basic reproduction number (R0) estimates indicate an initial value between 2 and 3.5 in most cities on this date . The mean period for R0 estimates to decrease to 80% and 50% of initial values in cities were an average of 14.73 and 19.62 days, respectively .
CONCLUSIONS: Our model estimates the complete spatiotemporal epidemiological characteristics of the outbreak in a space-time domain, and the findings will help enhance a comprehensive understanding of the outbreak and inform the strategies of prevention and control in other countries worldwide.