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Infections with ‘U.K. Variant’ B.1.1.7 Have Greater Risk of Mortality

Posted on by Dr. Francis Collins

One coronavirus in a group looks different and is labeled B.1.1.7 variant. Lines radiate from Britain on a map.

Since the genome sequence of SARS-CoV-2, the virus responsible for COVID-19, was first reported in January 2020, thousands of variants have been reported. In the vast majority of cases, these variants, which arise from random genomic changes as SARS-CoV-2 makes copies of itself in an infected person, haven’t raised any alarm among public health officials. But that’s now changed with the emergence of at least three variants carrying mutations that potentially make them even more dangerous.

At the top of this short list is a variant known as B.1.1.7, first detected in the United Kingdom in September 2020. This variant is considerably more contagious than the original virus. It has spread rapidly around the globe and likely accounts already for at least one-third of all cases in the United States [1]. Now comes more troubling news: emerging evidence indicates that infection with this B.1.1.7 variant also comes with an increased risk of severe illness and death [2].

The findings, reported in Nature, come from Nicholas Davies, Karla Diaz-Ordaz, and Ruth Keogh, London School of Hygiene and Tropical Medicine. The London team earlier showed that this new variant is 43 to 90 percent more transmissible than pre-existing variants that had been circulating in England [3]. But in the latest paper, the researchers followed up on conflicting reports about the virulence of B.1.1.7.

They did so with a large British dataset linking more than 2.2 million positive SARS-CoV-2 tests to 17,452 COVID-19 deaths from September 1, 2020, to February 14, 2021. In about half of the cases (accounting for nearly 5,000 deaths), it was possible to discern whether or not the infection had been caused by the B.1.1.7 variant.

Based on this evidence, the researchers calculated the risk of death associated with B.1.1.7 infection. Their estimates suggest that B.1.1.7 infection was associated with 55 percent greater mortality compared to other SARS-CoV-2 variants over this time period.

For a 55- to 69-year-old male, this translates to a 0.9-percent absolute, or personal, risk of death, up from 0.6 percent for the older variants. That means nine in every 1,000 people in this age group who test positive with the B.1.1.7 variant would be expected to die from COVID-19 a month later. For those infected with the original virus, that number would be six.

The U.S. percentage of B.1.1.7 started near zero on January 2, 2021 but by March 13 was over 20%.
Adapted from Centers for Disease Control and Prevention

These findings are in keeping with those of another recent study reported in the British Medical Journal [4]. In that case, researchers at the University of Exeter and the University of Bristol found that the B.1.1.7 variant was associated with a 64 percent greater chance of dying compared to earlier variants. That’s based on an analysis of data from more than 100,000 COVID-19 patients in the U.K. from October 1, 2020, to January 28, 2021.

That this variant comes with increased disease severity and mortality is particularly troubling news, given the highly contagious nature of B.1.1.7. In fact, Davies’ team has concluded that the emergence of new SARS-CoV-2 variants now threaten to slow or even cancel out improvements in COVID-19 treatment that have been made over the last year. These variants include not only B1.1.7, but also B.1.351 originating in South Africa and P.1 from Brazil.

The findings are yet another reminder that, while we’re making truly remarkable progress in the fight against COVID-19 with increasing availability of safe and effective vaccines (more than 45 million Americans are now fully immunized), now is not the time to get complacent. This devastating pandemic isn’t over yet.

The best way to continue the fight against all SARS-CoV-2 variants is for each one of us to do absolutely everything we can to stop their spread. This means that taking the opportunity to get vaccinated as soon as it is offered to you, and continuing to practice those public health measures we summarize as the three Ws: Wear a mask, Watch your distance, Wash your hands often.


[1] US COVID-19 Cases Caused by Variants. Centers for Disease Control and Prevention.

[2] Increased mortality in community-tested cases of SARS-CoV-2 lineage B.1.1.7. Davies NG, Jarvis CI; CMMID COVID-19 Working Group, Edmunds WJ, Jewell NP, Diaz-Ordaz K, Keogh RH. Nature. 2021 Mar 15.

[3] Estimated transmissibility and impact of SARS-CoV-2 lineage B.1.1.7 in England. Davies NG, Abbott S, Barnard RC, Jarvis CI, Kucharski AJ, Munday JD, Pearson CAB, Russell TW, Tully DC, Washburne AD, Wenseleers T, Gimma A, Waites W, Wong KLM, van Zandvoort K, Silverman JD; CMMID COVID-19 Working Group; COVID-19 Genomics UK (COG-UK) Consortium, Diaz-Ordaz K, Keogh R, Eggo RM, Funk S, Jit M, Atkins KE, Edmunds WJ.
Science. 2021 Mar 3:eabg3055.

[4] Risk of mortality in patients infected with SARS-CoV-2 variant of concern 202012/1: matched cohort study. Challen R, Brooks-Pollock E, Read JM, Dyson L, Tsaneva-Atanasova K, Danon L. BMJ. 2021 Mar 9;372:n579.


COVID-19 Research (NIH)

Nicholas Davies (London School of Hygiene and Tropical Medicine, U.K.)

Ruth Keogh (London School of Hygiene and Tropical Medicine, U.K.)


  • Howard C. says:

    You have to ask the question does socialized medicine in the UK have anything to do with the higher mortality rate.

  • Barbara Lewis says:

    For God sakes tell us whether having had only one shot so far gives us any immunity to the variant you describel

    • Steve White says:

      I am not a scientist but I want to point out, your question does not say WHICH shot – this may be important, it may be some shots will do more against a particular variant than others. My private theory is a lot of the vaccines are not going to stop the variants first identified in South Africa and Brazil very well.
      However, I have read the B1117 variant is pretty well stopped by the BioNTech/Pfizer shot. And that most of the immunity comes from one shot. So, if you got that shot I think it will make you a lot safer than without it, but again that is just my reading as a total layman.

  • Steve White says:

    I am glad the DIrector is very openly describing the threat from the new variant, B1117.
    However, B117, by all reports I have seen so far, is fully vulnerable to the vaccines we use in the US. The apparently very successful vaccine push our Federal government is conducting – claiming 3M per day recently – will soon put an end to B1117 in the US. Obviously, thousands of people will die of Covid 19, unnecessarily, by people relaxing their guard too soon, and that is very bad, but still the threat will soon end. I am skeptical all the concern, advice to wear two masks, objection to reopening, and so forth is due to B1117.

    I am still concerned CDC has not been fully open about the threat from the other variants. The huge 2nd outbreak in Brazil, of P1 variant this time, proves people who got sick less than a year ago with the original variant, can get sick again with P1. I feel we should have sent a plane load of Pfizer and Moderna, and then JJ vaccines, to Manaus to vaccinate high risk people during their outbreak and see if those vaccines protect them. Ditto for those parts of South Africa most effected by B1351.

    I do not see how we can make reasonable plans for the epidemic here without knowing how effective our vaccines will be against the variants. I have faith our people are trying to answer these questions, but it is not at all clear they are doing all they can to answer them RAPIDLY.

    To bottom line it – if the vaccines we use here are really ineffective against those variants (and the “New York” variant which is probably reinfecting people who were infected before in New England) then we need to have a Plan B – which I also know we are working on, but I think it is bad messaging for the authorities to not tell us what is going on. Senators are challenging the need to wear masks, and frankly, they appear correct, if they were fully vaccinated, and the only variants here were 95% prevented by the vaccines. Most people will agree I think -they need to be told about the vaccine evading variants in very definite terms now. The President tweeted a mention of variants but did not go into adequate detail.

    • Steve White says:

      I wanted to add – we have a lot of homegrown variant trouble, but it may be the big outbreak in Mexico is due to some kind of vaccine evading variant. We need to know if such a variant is down there, and how common it is, to determine how important it is to screen people coming in. Genotype screening of the people we can find will give us a pretty good picture of the risk, but it appears that is not being done.

      • Sara Jeanne Foehner says:

        i agree with most of what you said, Steve. Except where you said. that it is not at all clear that our scientists are trying to answer these questions rapidly. How would you know this? Are you a research scientist? Do you work for NIH or Pfizer or someone similar? Do you have any scientific or medical education?

  • BMiller says:

    There is an enormous amount of genericized assumptions with this article and statements made within. The original papers on the variants do not come to these conclusions. Not factoring in the demographics, locations, co-morbidities, and environment of outcomes and deaths leaves this as nothing but circumstantial evidence that the variants are either more contagious or cause for more severe outcomes. It’s a misuse of authority to make these claims knowing the potential for negative outcome. These are the reasons the scientific community no longer looks to the NIH or CDC for credible information.

  • Jon Gustafson says:

    There is an urgent need in the US for: 1) Agreement on which model(s) will be used to estimate variant dominance since there is little consistency and broad disparity between federal authorities reporting % variant dominance in the wild. 2) Increased genomic screening so that the preferred model can be robustly informed. 3) Increased data availability at the county level regarding the frequency of genomic screening, frequency of variant occurrence and standing variant prevalence.

    Here is the situation on the ground: The public is largely left to local reporting of variance presence in their communities. There is no single authoritative federal voice advising state health and education departments of relative risk from variants. If the risk of transmission of B.1.1.7 is significantly higher than those that have already contributed to more than half a million deaths nationwide, it would seem important to identify and/or highlight existing and/or improved safety measures to reduce likelihood of transmission. Any refined messaging regarding improved safety measures will run against skepticism based on conflicting federal sources on the subject of variants at large.

    Thank you for your leadership.

    • Steve White says:

      Thank you for your post. I have been calling my local county public health department. Alameda County California, a large urban county which identified cases of P1 and B1351 quite a while back, in people who did not travel internationally, to find out how common the two variants had become. They claim to have no information, which I frankly do not believe,as Stanford has been doing a lot of testing, and Stanford is 30 minutes drive from here. But I do not doubt their information is incomplete.
      We need to know both personal risk, and, as the escape variants become more common, local area risk, based on variant frequency and local vaccination and previous infection rates. Not just for now. If we have a continuing problem with escape variants, we will need this for the indefinite future.

  • John Hasty BS (ASCP) Retired says:

    Why is it that you can have asymptomatic COVID-19, but there is no mention of asymptomatic blood clots cause by the mRNA vaccines? All of the news is focused on the severe clots reported.

  • says:

    Older variants have not a 0,6 % risk of death, it is more like 0,3-4% from newer studies. The “model” that claims that the B.1.1.7 variant is more deadly is only a model based on a lot of assumptions. Noone can seriously claim, what this article claims, there are just hypoteses yet unproven.

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