Assessing spread risk of Wuhan novel coronavirus within and beyond China, January-April 2020: a travel network-based modelling study

Shengjie Lai; Isaac Bogoch; Nick Ruktanonchai; Alexander Watts; Xin Lu; Weizhong Yang; Hongjie Yu; Kamran Khan; Andrew J Tatem

To define the connectivity and risk of 2019n-CoV spreading from Wuhan and high-risk secondary cities defined above, into the cities beyond mainland China, we obtained aggregated itinerary data from the International Air Travel Association (IATA) [13] . IATA data accounts for approximately 90% of passenger travel itineraries on commercial flights, and these data represent direct origin (Wuhan) to destination trips, and indirect trips that originated in Wuhan, but had connecting flights to a final destination. We quantified monthly volumes of airline travellers departing Wuhan and high-risk secondary cities from February 1 st , 2018, through April 30 th , 2018. With the assumption that the population movements around the LNY holiday in 2020 was consistent with the pattern in 2018, all final destinations were ranked by volumes of airline travellers, and the relative risk of importation was defined as the percentage of airline travellers received by each destination city out of the total volume of travellers leaving high-risk cities in China.