Evaluating new evidence in the early dynamics of the novel coronavirus COVID-19 outbreak in Wuhan, China with real time domestic traffic and potential asymptomatic transmissions

Can Zhou

The real time traffic is a crucial piece of information to understand the dynamics and the spread of the COVD-19 outbreak in Wuhan. As a major traffic hub in central China, Wuhan's capacity to drive significant population flows is driving the accelerated spread of the disease domestically. Real time traffic flow out of Wuhan was found to differ significantly from its historical patterns. From Jan. 1, 2020, when the Huanan seafood market was disinfected, to Jan. 23, 2020, when the city of Wuhan was quarantined, the net traffic flow has always been outwards. During this period, the overall net outflow is estimated to be over 9 million individuals. On Feb. 11, 2020, the disease has already spread to all provinces of China with 44,653 confirmed cases in China. In early January, the number of cases in Wuhan is only growing linearly ( Figure 9 ) and even appears to have stabilized days before Jan. 23, due to the accelerated outflow. It is thus very dangerous to overinterpret the temporal pattern of the number of cases without taking into account real time traffic.