High Contagiousness and Rapid Spread of Severe Acute Respiratory Syndrome Coronavirus 2

Emerg Infect Dis. 2020 Jul;26(7):1470-1477. doi: 10.3201/eid2607.200282. Epub 2020 Jun 21.

Abstract

Severe acute respiratory syndrome coronavirus 2 is the causative agent of the ongoing coronavirus disease pandemic. Initial estimates of the early dynamics of the outbreak in Wuhan, China, suggested a doubling time of the number of infected persons of 6-7 days and a basic reproductive number (R0) of 2.2-2.7. We collected extensive individual case reports across China and estimated key epidemiologic parameters, including the incubation period (4.2 days). We then designed 2 mathematical modeling approaches to infer the outbreak dynamics in Wuhan by using high-resolution domestic travel and infection data. Results show that the doubling time early in the epidemic in Wuhan was 2.3-3.3 days. Assuming a serial interval of 6-9 days, we calculated a median R0 value of 5.7 (95% CI 3.8-8.9). We further show that active surveillance, contact tracing, quarantine, and early strong social distancing efforts are needed to stop transmission of the virus.

Keywords: 2019 novel coronavirus disease; COVID-19; China; SARS-CoV-2; Wuhan; modeling; respiratory infections; severe acute respiratory syndrome coronavirus 2; transmission potential; viruses; zoonoses.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Basic Reproduction Number
  • Betacoronavirus*
  • COVID-19
  • China / epidemiology
  • Coronavirus Infections / epidemiology*
  • Coronavirus Infections / prevention & control
  • Coronavirus Infections / transmission
  • Disease Outbreaks
  • Humans
  • Models, Theoretical
  • Pandemics / prevention & control
  • Pneumonia, Viral / epidemiology*
  • Pneumonia, Viral / prevention & control
  • Pneumonia, Viral / transmission
  • SARS-CoV-2
  • Travel