Bingyi Yang, Sheena G. Sullivan, Zhanwei Du, Tim K. Tsang, and Benjamin J. Cowling
Figure. Association between international travel controls and local coronavirus disease (COVID-19) outbreaks in 165 countries, January 1–July 31, 2020. A) Temporal distribution of the international travel controls enacted by the studied countries. Data from (7). B) Distribution of the time between a country’s first COVID-19 case and its enactment of any or of the strongest international travel controls. C, D) Probability of reaching first local peak of COVID-19 cases by the time of implementing any (C) or the strongest (D) international travel controls, estimated by using the Kaplan-Meier survival function. Vertical dashed lines in panels B, C, and D indicate the date that Wuhan, China, underwent lockdown; vertical dotted lines indicate the date that the pandemic was declared.