Evolving Epidemiology and Impact of Non-pharmaceutical Interventions on the Outbreak of Coronavirus Disease 2019 in Wuhan, China

Chaolong Wang; Li Liu; Xingjie Hao; Huan Guo; Qi Wang; Jiao Huang; Na He; Hongjie Yu; Xihong Lin; An Pan; Sheng Wei; Tangchun Wu

Our SEIR model fit the observed data well, except for the outlier on February 1 (Fig. 4A ). The slight overprediction for the last five days (February 14-18) was likely due to the delay in laboratory confirmation of recent cases. The transmission rate decreased from 1.75 (95% CrI, 1.71 to 1.80) before January 23 to 0.58 (0.56 to 0.60) and 0.15 (0.13 to 0.17) after January 23 and February 2, respectively (Table S2) , which could be translated into R t of 3.88 (3.77 to 3.99), 3.86 (3.74 to 3.97), 1.26 (1.21 to 1.31), and 0.32 (0.28 to 0.37) for the four periods, respectively (Fig. 4B) . We estimated the number of cumulative ascertained cases till February 18 to be 49,943 (95% CrI, 43,577 to 56,635) if the trend of the third period was assumed (Fig. 4C) , or . CC-BY-NC-ND 4.0 International license It is made available under a author/funder, who has granted medRxiv a license to display the preprint in perpetuity.