Modelling the impact of urban bus transit on epidemic transmission

In response to the rapid spread of Covid-19 in Wuhan, China, the role of urban bus transit in accelerating epidemic transmission was investigated in this study. A modified susceptible–exposed–infective–removed model (F-SEIR) was developed to incorporate inter-regional population movements and in-vehicle transmission dynamics. The F-SEIR model leveraged detailed bus IC (integrated circuit) card data and GPS trajectories to simulate both passenger inter-region mobility and the epidemic transmission process within enclosed bus environments. The results showed that bus transit substantially accelerated the urban spread of the epidemic, as evidenced by the emergence of distinctive ‘fly dot’ clustering patterns. Importantly, the simulation indicated that restricting bus travel could have reduced the number of infections by approximately 18.6–28.3%, with earlier intervention strategies leading to even more significant declines in infection rates. The findings not only validate the F-SEIR model against the observed trends in Wuhan, but also provide executable insights for transportation managers and policy makers in optimising public transit operations during epidemics.