New York: The World Health Organization on Friday declared the recently-discovered B.1.1.529 strain of Covid-19 to be a variant of concern, renaming it Omicron.
"Based on the evidence presented indicative of a detrimental change in Covid-19 epidemiology... the WHO has designated B.1.1.529 as a variant of concern, named Omicron," the UN health agency said in a statement.
The variant has a "very unusual constellation" of mutations, which are concerning because they could help it evade the body's immune response and make it more transmissible, scientists told reporters at a news conference in South Africa.
South Africa has confirmed around 100 specimens as B.1.1.529, but the variant has also been found in Botswana and Hong Kong, with the Hong Kong case a traveller from South Africa.