Wed Feb 26 19:25:03 2020
<643f1644> <https://www.medrxiv.org/content/10.1101/2020.02.07.20021154v1|https://www.medrxiv.org/content/10.1101/2020.02.07.20021154v1>
— The Novel Coronavirus, 2019-nCoV, is Highly Contagious and More Infectious Than Initially Estimated
— The novel coronavirus (2019-nCoV) is a recently emerged human pathogen that has spread widely since January 2020. Initially, the basic reproductive number, R0, was estimated to be 2.2 to 2.7. Here we provide a new estimate of this quantity. We collected extensive individual case reports and estimated key epidemiology parameters, including the incubation period. Integrating these estimates and high-resolution real-time human travel and infection data with mathematical models, we estimated that the number of infected individuals during early epidemic double every 2.4 days, and the R0 value is likely to be between 4.7 and 6.6. We further show that quarantine and contact tracing of symptomatic individuals alone may not be effective and early, strong control measures are needed to stop transmission of the virus. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement SS and RK would like to acknowledge funding from DARPA (HR0011938513). CX acknowledges the support from the Laboratory Directed Research and Development (LDRD) Program at Los Alamos National Laboratory. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ### Author Declarations All relevant ethical guidelines have been followed; any necessary IRB and/or ethics committee approvals have been obtained and details of the IRB/oversight body are included in the manuscript. Yes All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as <http://ClinicalTrials.gov|ClinicalTrials.gov>. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All data is available in the main text or the supplementary materials.
<643f1644> R0 value is likely to be between 4.7 and 6.6