After R. Malone tt:
Summary As Sars-CoV-2 entered a highly susceptible human population, it has initially been spreading rapidly and in an uncontrollable way. This already explains why Sars-CoV-2 has been evolving rather slowly with no substantial selection of fitness-enhancing mutations occurring over the first 10 months of the pandemic (i.e., between December 2019 and October 2020). More infectious ‘variants of concern’ (VoCs, i.e., alpha [B.1.1.7], beta [B.1.351], gamma [P.1]) started to appear as of late 2020 and led to a steep increase in cases worldwide. Molecular epidemiologists have observed that mutations within the Sars-CoV-2 spike (S) protein of these emerging, more infectious lineages are converging to the same genetic sites, a phenomenon that coincided with a major evolutionary shift in the landscape of naturally selected Sars-CoV-2 mutations (1). Significant convergent evolution of more infectious circulating Sars-CoV-2 variants is not a neutral, host-independent evolutionary phenomenon that merely results from increased viral replication and ...
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