Early phylogenetic estimate of the effective reproduction number of SARS-CoV-2

J Med Virol. 2020 Jun;92(6):675-679. doi: 10.1002/jmv.25723. Epub 2020 Mar 3.

Abstract

To reconstruct the evolutionary dynamics of the 2019 novel-coronavirus recently causing an outbreak in Wuhan, China, 52 SARS-CoV-2 genomes available on 4 February 2020 at Global Initiative on Sharing All Influenza Data were analyzed. The two models used to estimate the reproduction number (coalescent-based exponential growth and a birth-death skyline method) indicated an estimated mean evolutionary rate of 7.8 × 10-4 subs/site/year (range, 1.1 × 10-4 -15 × 10-4 ) and a mean tMRCA of the tree root of 73 days. The estimated R value was 2.6 (range, 2.1-5.1), and increased from 0.8 to 2.4 in December 2019. The estimated mean doubling time of the epidemic was between 3.6 and 4.1 days. This study proves the usefulness of phylogeny in supporting the surveillance of emerging new infections even as the epidemic is growing.

Keywords: SARS-CoV-2; evolutionary dynamics; reproductive number.

MeSH terms

  • Base Sequence
  • Bayes Theorem
  • Betacoronavirus / classification
  • Betacoronavirus / genetics*
  • Betacoronavirus / isolation & purification
  • Betacoronavirus / pathogenicity
  • COVID-19
  • Coronavirus Infections / diagnosis
  • Coronavirus Infections / epidemiology*
  • Coronavirus Infections / transmission*
  • Coronavirus Infections / virology
  • Epidemiological Monitoring
  • Evolution, Molecular
  • Genome, Viral*
  • Humans
  • Information Dissemination
  • Models, Statistical*
  • Open Reading Frames
  • Pandemics*
  • Phylogeny
  • Pneumonia, Viral / diagnosis
  • Pneumonia, Viral / epidemiology*
  • Pneumonia, Viral / transmission*
  • Pneumonia, Viral / virology
  • RNA, Viral / genetics
  • SARS-CoV-2
  • Sequence Alignment
  • Sequence Homology, Nucleic Acid

Substances

  • RNA, Viral