Changing transmission dynamics of COVID-19 in China: a nationwide population-based piecewise mathematical modelling study

Abstract

The spatial patterns of disease spread were heterogeneous. The estimated controlled reproduction number () in the neighboring provinces of Hubei province were relatively large, and the nationwide reproduction number ? except for Hubei ? ranged from 0.98 to 2.74 with an average of 1.79 (95% CI 1.77?1.80). Infectivity was significantly greater for exposed than infectious individuals, and exposed individuals were predicted to have become the major source of infection after January 23. For the epidemic process, most provinces reached their epidemic peak before February 10, 2020. It is expected that the maximum number of infections will be approached by the end of March. The final infectious size is estimated to be about 58,000 for Wuhan, 20,800 for the rest of Hubei province, and 17,000 for the other provinces in mainland China. Moreover, the estimated number of the exposed individuals is much greater than the officially reported number of infectious individuals in Wuhan on January 10, 2020.