A retrospective analysis of the dynamic transmission routes of the COVID‐19 in mainland China

Abstract

The fourth outbreak of the Coronaviruses, known as the COVID-19, has occurred inWuhan city of Hubei province in China in December 2019. We propose a time-varying sparse vector autoregressive (VAR) model to retrospectively analyze and visualize the dynamic transmission routes of this outbreak in mainland China over January 31–February 19, 2020. Our results demonstrate that the infuential inter-location routes from Hubei have become unidentifable since February 4, 2020, whereas the self-transmission in each provincial-level administrative region (location, hereafter) was accelerating over February 4–15, 2020. From February 16, 2020, all routes became less detectable, and no infuential transmissions could be identifed on February 18 and 19, 2020. Such evidence supports the efectiveness of government interventions, including the travel restrictions in Hubei. Implications of our results suggest that in addition to the origin of the outbreak, virus preventions are of crucial importance in locations with the largest migrant workers percentages (e.g., Jiangxi, Henan andAnhui) to controlling the spread of COVID-19.