Intended for healthcare professionals

CCBY Open access

Risk of mortality in patients infected with SARS-CoV-2 variant of concern 202012/1: matched cohort study

BMJ 2021; 372 doi: (Published 10 March 2021) Cite this as: BMJ 2021;372:n579

Read our latest coverage of the coronavirus outbreak

Linked Editorial

Covid-19: variants and vaccination

Linked Opinion

Increased risk of mortality in patients infected with SARS-CoV-2 variant of concern 202012/1

  1. Robert Challen, postdoctoral research associate123,
  2. Ellen Brooks-Pollock, senior lecturer in veterinary public health345,
  3. Jonathan M Read, senior lecturer in epidemiology and biostatistics36,
  4. Louise Dyson, associate professor in epidemiology37,
  5. Krasimira Tsaneva-Atanasova, professor of mathematics for healthcare18,
  6. Leon Danon, associate professor in infectious disease epidemiology and data analytics3589
  1. 1College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, UK
  2. 2Somerset NHS Foundation Trust, Taunton, UK
  3. 3Joint Universities Pandemic and Epidemiological Research (JUNIPER consortium)
  4. 4University of Bristol, Bristol Veterinary School, Langford, Bristol, UK
  5. 5Bristol Medical School, Population Health Sciences, University of Bristol, Bristol, UK
  6. 6Lancaster Medical School, Lancaster University, Bailrigg, Lancaster, UK
  7. 7The Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, School of Life Sciences and Mathematics Institute, University of Warwick, Coventry, UK
  8. 8The Alan Turing Institute, British Library, London, UK
  9. 9Department of Engineering Mathematics, University of Bristol, Bristol, UK
  1. Correspondence to: R Challen rc538{at} (or @rjchallen on Twitter)
  • Accepted 25 February 2021


Objective To establish whether there is any change in mortality from infection with a new variant of SARS-CoV-2, designated a variant of concern (VOC-202012/1) in December 2020, compared with circulating SARS-CoV-2 variants.

Design Matched cohort study.

Setting Community based (pillar 2) covid-19 testing centres in the UK using the TaqPath assay (a proxy measure of VOC-202012/1 infection).

Participants 54 906 matched pairs of participants who tested positive for SARS-CoV-2 in pillar 2 between 1 October 2020 and 29 January 2021, followed-up until 12 February 2021. Participants were matched on age, sex, ethnicity, index of multiple deprivation, lower tier local authority region, and sample date of positive specimens, and differed only by detectability of the spike protein gene using the TaqPath assay.

Main outcome measure Death within 28 days of the first positive SARS-CoV-2 test result.

Results The mortality hazard ratio associated with infection with VOC-202012/1 compared with infection with previously circulating variants was 1.64 (95% confidence interval 1.32 to 2.04) in patients who tested positive for covid-19 in the community. In this comparatively low risk group, this represents an increase in deaths from 2.5 to 4.1 per 1000 detected cases.

Conclusions The probability that the risk of mortality is increased by infection with VOC-202012/01 is high. If this finding is generalisable to other populations, infection with VOC-202012/1 has the potential to cause substantial additional mortality compared with previously circulating variants. Healthcare capacity planning and national and international control policies are all impacted by this finding, with increased mortality lending weight to the argument that further coordinated and stringent measures are justified to reduce deaths from SARS-CoV-2.


  • Contributors: RC and LDanon designed the study. All authors conceived the article. RC analysed the data and wrote the initial draft of the manuscript. KTA, EB-P, LDanon, JMR, and LDyson commented on, and revised, the manuscript. All authors read and approved the final manuscript. RC is the guarantor. The views presented here are those of the authors and should not be attributed to Somerset Foundation NHS Trust or Global Digital Exemplar. The corresponding author attests that all listed authors meet authorship criteria and that no others meeting the criteria have been omitted.

  • Funding: RC and KTA were supported by the Engineering and Physical Sciences Research Council (EPSRC; grants EP/N014391/1, EP/T017856/1) and NHS England, Global Digital Exemplar programme. LDanon and KTA were supported by The Alan Turing Institute (EPSRC grant EP/N510129/1). LDanon, RC, and EBP are supported by the Medical Research Council (MRC; MC/PC/19067). JMR is supported by EPSRC (EP/N014499/1) and MRC (MR/S004793/1, MR/V028456/1). EBP was partly supported by the National Institute for Health Research Health Protection Research Unit in Behavioural Science and Evaluation at University of Bristol, in partnership with Public Health England. LDanon, EBP, JMR, and LDyson are further supported by MRC (MR/V038613/1), and LDanon by EPSRC EP/V051555/1. LDyson also received support through the MRC through the covid-19 rapid response rolling call (grant No MR/V009761/1).

  • Competing interests: All authors have completed the ICMJE uniform disclosure form at and declare: support from the Engineering and Physical Sciences Research Council, NHS England, Global Digital Exemplar programme, Alan Turing Institute, Medical Research Council, and National Institute for Health Research Health Protection Research Unit in Behavioural Science and Evaluation, in partnership with Public Health England; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.

  • Ethical approval: The data were supplied from the Second Generation Surveillance System (SGSS) database and death reports after anonymisation under strict data protection protocols agreed between the University of Exeter and Public Health England. The ethics of the use of these data for these purposes was agreed by Public Health England with the UK government SPI-M(O)/SAGE committees. The research was assessed as not needing NHS research ethics committee review.

  • Data sharing: The data analysis code is available at doi:10.5281/zenodo.4543510. Data are available to members of universities who have data sharing agreements in place with Public Health England.

  • The lead author (RC) affirms that the manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.

  • Dissemination to participants and related patient and public communities: Direct dissemination to study participants is not possible. Preprint versions of this analysis are available on MedRxiv (

  • Provenance and peer review: Not commissioned; externally peer reviewed.

This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BY 4.0) license, which permits others to distribute, remix, adapt and build upon this work, for commercial use, provided the original work is properly cited. See:

View Full Text