Zhao et al.7  China  10–24 January 2020  Statistical exponential growth model method adopting serial interval from SARS (mean = 8.4 days, SD = 3.8 days) and MERS (mean = 7.6 days, SD = 3.4 days)  Corresponding to 2-fold increase in the reporting rateR0 = 1/M(−𝑟)𝑟 =intrinsic growth rateM = moment generating function  3.58  2.89–4.39