 468 confirmed cases of coronavirus disease in China as of February 8, 2020 had a mean serial interval of 3.96 days, 95% CI 3.53 to 4.39 days, and SD 4.75 days, 95% CI 4.46 to 5.07 days, with 12.6% of case reports indicating pre-symptomatic transmission. This article was authored by Jianwei Du, Xiaokusu, Yiwu, and others.