Delta
It was first discovered in India. Descendant of lineage B.1.617, which also includes the Kappa variant under investigation, it was first discovered in October 2020 and has since spread internationally.
Alpha
First detected in October 2020 during the COVID-19 pandemic in the United Kingdom from a sample taken the previous month in Kent, lineage B.1.1.7, labelled Alpha variant by the World Health Organization (WHO), was previously known as the first Variant Under Investigation in December 2020 (VUI – 202012/01) and later notated as VOC-202012/01.
Omicron
The Omicron variant, known as lineage B.1.1.529, was declared a variant of concern by the World Health Organization (WHO) on 26 November 2021.
