The reproductive number of the Delta variant of SARS-CoV-2 is far higher compared to the ancestral SARS-CoV-2 virus

J Travel Med. 2021 Oct 11;28(7):taab124. doi: 10.1093/jtm/taab124.


The Delta variant is now replacing all other SARS-CoV-2 variants. We found a mean R0 of 5.08, which is much higher than the R0 of the ancestral strain of 2.79. Rapidly ramping up vaccine coverage rates while enhancing public health and social measures is now even more urgent and important.

Keywords: Alpha variant; B1.617.2; COVID-19; Delta variant; R0; SARS-CoV-2; Wuhan; basic reproductive number; epidemic potential; pandemic; transmissibility; variants of concerns.

MeSH terms

  • Basic Reproduction Number*
  • COVID-19
  • Humans
  • SARS-CoV-2* / physiology