Assessing the impact of reduced travel on exportation dynamics of novel coronavirus infection (COVID-19)

Asami Anzai; Tetsuro Kobayashi; Natalie M. Linton; Ryo Kinoshita; Katsuma Hayashi; Ayako Suzuki; Yichi Yang; Sungmok Jung; Takeshi Miyama; Andrei R. Akhmetzhanov; Hiroshi Nishiura

By early February 2020, it was evident that the incidence of novel coronavirus infections (COVID-19) was exponential [1] . Accelerated by human migration, exported cases have been reported in various regions of the world, including Europe, Asia, North America, and Oceania [2] . To minimize the rapid growth of cases via human-to-human transmission [3] [4] [5] , the government of China suspended all modes of transportation to and from Wuhan on 23 January 2020-including vehicles, trains, and flights-expecting that the intervention would prevent further spread of the disease [6] . As of 12 February 2020, two additional cities outside of Hubei Province-Wenzhou (Zhejiang Province) and Shenzhen (Guangdong Province)-have been placed on complete lockdown (i.e. no cross-border movement to and from the closed city) to prevent further spatial spread of COVID-19. To our knowledge, such drastic movement restrictions are a historical first.