Increased mortality in community-tested cases of SARS-CoV-2 lineage B.1.1.7

Nature. 2021 May;593(7858):270-274. doi: 10.1038/s41586-021-03426-1. Epub 2021 Mar 15.


SARS-CoV-2 lineage B.1.1.7, a variant that was first detected in the UK in September 20201, has spread to multiple countries worldwide. Several studies have established that B.1.1.7 is more transmissible than pre-existing variants, but have not identified whether it leads to any change in disease severity2. Here we analyse a dataset that links 2,245,263 positive SARS-CoV-2 community tests and 17,452 deaths associated with COVID-19 in England from 1 November 2020 to 14 February 2021. For 1,146,534 (51%) of these tests, the presence or absence of B.1.1.7 can be identified because mutations in this lineage prevent PCR amplification of the spike (S) gene target (known as S gene target failure (SGTF)1). On the basis of 4,945 deaths with known SGTF status, we estimate that the hazard of death associated with SGTF is 55% (95% confidence interval, 39-72%) higher than in cases without SGTF after adjustment for age, sex, ethnicity, deprivation, residence in a care home, the local authority of residence and test date. This corresponds to the absolute risk of death for a 55-69-year-old man increasing from 0.6% to 0.9% (95% confidence interval, 0.8-1.0%) within 28 days of a positive test in the community. Correcting for misclassification of SGTF and missingness in SGTF status, we estimate that the hazard of death associated with B.1.1.7 is 61% (42-82%) higher than with pre-existing variants. Our analysis suggests that B.1.1.7 is not only more transmissible than pre-existing SARS-CoV-2 variants, but may also cause more severe illness.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • COVID-19 / mortality*
  • COVID-19 / virology*
  • Child
  • Child, Preschool
  • England / epidemiology
  • Ethnicity
  • Evolution, Molecular
  • Female
  • Homes for the Aged
  • Humans
  • Infant
  • Male
  • Middle Aged
  • Phylogeny*
  • Proportional Hazards Models
  • Risk Assessment
  • SARS-CoV-2 / classification*
  • SARS-CoV-2 / genetics
  • SARS-CoV-2 / isolation & purification
  • SARS-CoV-2 / pathogenicity*
  • Survival Analysis
  • Time Factors
  • Young Adult