What are the strains of SARS-CoV-2?
Three SARS-CoV-2 variants have been identified (A, B, and C), which differ in their amino acid sequences. The ancestral type A and the mutated type C are found in significant proportions outside East Asia, mainly in Europe and in the USA. Type B, which has mutated and spread, is the most common strain in East Asia.7 Continuous genome sequencing of virus mutations is needed to monitor the pandemic.