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Covid-19: New UK variant may be linked to increased death rate, early data indicate

BMJ 2021; 372 doi: (Published 26 January 2021) Cite this as: BMJ 2021;372:n230

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Covid-19 and evolutionary pressure - can we predict which genetic dangers lurk beyond the horizon?

Dear editor

As Charles Darwin taught us, the evolution of living creatures is inevitable. It is important to recognise that the evolutionary process can progress down many different pathways and - whether or not philosophers and biologists consider viruses to be “living creatures”(1) - in the real world natural selection certainly applies as much to the covid-19 virus as it does to any living entity, including human beings.

Given the view that covid-19 quite possibly first came into existence through the chance encounter of a bat and a pangolin, (2) and in light of the recent emergence of at least three new (and potentially very dangerous) covid-19 variants independently around the world, (3) when it comes to anticipating the next steps in this unfolding human tragedy, thinking caps need to become red-hot and scientific imaginations need to be exercised like never before.

For example, could at some point in the future human-sourced covid-19 re-enter other animal species and – as already appears to have happened with the bat and the pangolin scenario - encounter and combine with other animal-sourced coronaviruses to create yet more variants, some of which may prove to be dangerous to humans? This is not an outlandish idea - events of this type happen all the time with influenza,(4) and have considerable proven potential to damage human health. With this in mind, there have already been covid-19 related suspicions around the mink.(5)

Covid-19 represents a clear and present danger. All things are possible, and no possibilities can be discounted without sufficient evidence to do so. While engaging in the process of blue-skies thinking is a long and tough road to follow,(6) it nevertheless absolutely has to be followed if the human race wants to get ahead of the covid-19 curve, and for maximum chances of success the effort undoubtedly has to be international and inclusively world-wide.(7)


Competing interests: No competing interests

26 January 2021
Stephen T Green
Honorary Professor of International Health
Dr Lorenzo Cladi
Sheffield Hallam University & the University of Plymouth