Updated Jan. 15, 2021 Multiple SARS-CoV-2 variants are circulating globally. Several new variants emerged in the fall of 2020, most notably: • In the United Kingdom (UK), a new variant of SARS-CoV-2 (known as 20I/501Y.V1, VOC 202012/01, or B.1.1.7) emerged with an unusually large number of mutations. This variant has since been detected in numerous countries around the world, including the United States (US) and Canada. • In South Africa, another variant of SARS-CoV-2 (known as 20H/501Y.V2 or B.1.351) emerged independently of B.1.1.7. This variant shares some mutations with B.1.1.7. Cases attributed to this variant have been detected outside of South Africa. • In Brazil, a variant of SARS-CoV-2 (known as P.1) emerged and was identified in four travelers from Brazil, who were tested during routine screening at Haneda airport outside Tokyo, Japan. This variant has 17 unique mutations, including three in the receptor binding domain of the spike protein.

Emerging Variants -- Why Strain Surveillance is Important for Public Health -- Strain Surveillance in the US.

Stephen B. Thacker CDC Library collection