Varinets of COVID-19

Omicron and BA.2

There’s still a lot to learn about Omicron (BA.1) and its subvariant, BA.2, which surpassed the original Omicron strain in March to become the predominant variant in the U.S.

Delta (B.1.617.2) was first identified in India in late 2020; it soon spread throughout the world, becoming what was the predominant version of the coronavirus—until Omicron took its place in mid-December.

Delta AY.4.2*

Delta AY.4.2, sometimes referred to—incorrectly—as Delta Plus, was actually the most prominent of a number of Delta offshoots, some of which had mutations new to Delta but that were found in other variants.

Beta

This variant, or B.1.351, was identified in South Africa at the end of 2020 and spread to other countries. Experts had been concerned about its several mutations and its potential to evade antibodies.