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Coronavirus disease (COVID-19): Virus Evolution               1

            When a virus replicates or makes copies of itself, it sometimes changes a little bit. These changes are called “mutations.”
            A virus with one or several new mutations is referred to as a “variant” of the original virus.

            The more viruses circulate, the more they may change. These changes can occasionally result
            in a virus variant that is better adapted to its environment compared to the original virus.
            This process of changing and selection of successful variants is called “virus evolution.”




























                       Structure of SARS-CoV-2                               Structure of B117 Variant

                                           Table 1: Summary of new Covid-19 variants  2
               Commonly used name     B117                    B1351                   P1
               Country of first detection   UK                South Africa            Brazil

               Official name          B.1.1.7                 B.1.351                 P.1
               Other names used in the          N501Y.V1                       N501Y.V2                        N501Y.V3
               scientific literature   20B/501Y.V1                                 20H/501Y.V2                                 VOC 202012/3
                                      VOC 202012/1            VOC 202012/2
               Mutations              23                      21                      17
               Spike mutations        8                       9                       10
               Key receptor binding domain   69/70 deletion, P681H, A570D,   E484K, K417N,   E484K, K417N,
               (RBD), spike mutations beyond
                                      Y144 deletion, A570D    ORF1b deletion          ORF1b deletion
               N501Y in all
               Other mutations, including            T716I, S982A, D1118H   L18F, D80A, D215G, ∆242-244,   L18F, T20N, P26S, D138Y, R190S,
               N-terminal                                     R264I, A701V            H655Y
               Transmissibility       > 50% increased         Not established         Not established
               Lethality              Not resolved            No clear evidence       No clear evidence
               Immune escape          Partial reduction of efficacy     Partial reduction of efficacy in 3   Not established
                                      Novavax trial: (96% to 86%)  vaccine trials
                                      AstraZeneca trial: (84% to 75%)
               Countries reported     82                      40                      18

                                                  *The information is valid as of 19 February 2021 and will be updated from time to time by https://covidreference.com
              References:-
              1. WHO: Retrieved from https://www.who.int/news-room/q-a-detail/sars-cov-2-evolution
              2. Kamps, B. S., & Hoffmann, C. (2021). COVID Reference. Retrieved from https://amedeo.com/CovidReference06.pdf
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