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

Wuhan is central China's transportation hub with a population of 11 million residents and a large number of higher-education students (~1.3 million in 89 universities and colleges), a particularly mobile population [7] . Beyond these factors, viral spread was likely exacerbated further by the surge in domestic and international travel during the 40-day Lunar New Year (LNY) celebrations (from January 10 th , 2020 to February 18 th , 2020) -the largest annual human migration in the world, comprised of hundreds of millions of people travelling across the country. As of February 4 th , 2020, China has reported 20,530 confirmed cases and 23,314 suspected cases with 2019-nCoV infections [8] . Of the confirmed cases, 2788 are severe and 426 people have died. Most cases were reported from Wuhan and other cities in Hubei Province, and all provinces have confirmed cases imported from Wuhan and secondary transmission has been reported in some provinces. Additionally, there were 153 cases reported in 23 countries outside of China, with most having a travel history involving Wuhan [6] .