Since its emergence in December 2019, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide, causing a global pandemic (coronavirus disease-19 or COVID-19) with more than 188 million confirmed infections and more than 4 million fatalities (as of July 19, 2021) (https://covid19.who.int). While the majority of the infections are asymptomatic or manifest in mild to moderate forms, a small percentage of people develop severe respiratory illness with a fatal outcome.
Image: Figure 1 Key mutations in the spike protein of SARS-CoV Variants of Concern (VoC) (B.1.1.7, B.1.351, B.1.1.248, and B.1.617.2) and Variants of Interest (B.1.526, B.1.427, and B.1.429). Mutations occur on all spike protein subunits. Mutations in other areas of the genome have been identified and are currently under investigation.