What are variants of SARS-COV-2, the virus that causes COVID-19?
It is normal for viruses to change and evolve as they spread between people over time. When these changes become significantly different from the original virus, they are known as “variants.” To identify variants, scientists map the genetic material of viruses (known as sequencing) and then look for differences between them to see if they have changed.
Since the SARS-CoV-2 virus, the virus that causes COVID-19, has been spreading globally, variants have emerged and been identified in many countries around the world.
The current global epidemiology of SARS-CoV-2 is characterized by the predominance of the Delta variant, a declining trend in the proportion of Alpha, Beta and Gamma variants, and the emergence of Omicron, which was designated as a variant of concern (VOC) by WHO on November 26, 2021.