Discussion: While both V and A, as well as G are in the non-polar hydrophobic amino acid group and no evidence shows that the double mutations of V213A and D614G affect the severity and lethality of COVID-19 patients, further investigations are necessary to determine whether these dual mutations (V213A and D614G in spike protein) or even triple mutations (V213A and D614G in spike protein and V47A in NS2) associated with increased risk of mortality in COVID-19 patients.

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