We note that WHO reported the basic reproduction number for the human-to-human (direct) transmission ranged from 1.4 to 2.5 (World Health Organization, 2020b), which is marginally lower than ours. However, many of the existing online preprints estimate the mean R 0 ranging from 2 to 5 (Imai et al., 2020, Riou and Althaus, 2020, Read et al., 2020, Shen et al., 2020), which is largely consistent with our results.