The Novel Coronavirus, 2019-nCoV, is Highly Contagious and More Infectious Than Initially Estimated

Steven Sanche; Yen Ting Lin; Chonggang Xu; Ethan Romero-Severson; Nick Hengartner; Ruian Ke

Using the exponential growth rate, we next estimated the range of the basic reproductive number, R0. It has been shown that this estimation depends on the distributions of the latent period (defined as the period between the times when an individual infected and become infectious) and the infectious period (14) . For both periods, we assumed a gamma distribution and varied the mean and the shape parameter of the gamma distributions in a large range to reflect the uncertainties in these distributions (see Supplementary Materials). It is not clear when an individual becomes infectious; thus, we considered two scenarios: 1) the latent period is the same as the incubation period, and 2) the latent period is 2 days shorter than the incubation period, i.e. individuals start to transmit 2 days before symptom onset. Integrating uncertainties in the exponential growth rate estimated from the 'first arrival' approach and the uncertainties All rights reserved. No reuse allowed without permission. author/funder, who has granted medRxiv a license to display the preprint in perpetuity.