The sub-lineages of the Omicron variant

How many different lineages does Omicron have and how are they different from each other?

In late November 2021, the World Health Organization designated the lineage B.1.1.529 of SARS-CoV-2 as a Variant of Concern (VoC) and assigned it the Greek alphabet Omicron. This variant was initially uncovered by researchers based on genomes from Southern Africa as well as travellers from the region and was characterised by a strikingly large number of mutations, particularly in its spike protein. The Omicron variant has now been detected in over 130 countries . The variant is now present in all seven continents and associated with an uptick of COVID-19 cases in the regions where it has been detected, including infections in fully vaccinated individuals or people who were previously infected with other variants of SARS-CoV-2. Omicron continues to dominate the pandemic in most regions since early 2022, although the massive surges seen in many countries have already peaked.

The timely detection and reporting of Omicron was a result of the efforts of researchers from South Africa, Botswana and Hong Kong who shared the initial genome sequences of the variant on GISAID, a database in which researchers from all over the world deposit sequencing data of SARS-CoV-2.