The World Health Organization on Friday assigned the Greek letter omicron to a newly identified Covid variant in South Africa.
The U.N. health agency recognized the strain, previously referred to as lineage B.1.1.529, as a variant of concern.
Health experts are deeply concerned about the transmissibility of the omicron variant given that it has an unusual constellation of mutations and a profile that is different from other variants of concern.
“Omicron, B.1.1.529, is named as a variant of concern because it has some concerning properties,” Maria Van Kerkhove, the WHO’s technical lead on Covid-19, said in a video published on Twitter. “This variant has a large number of mutations, and some of these mutations have some worrying characteristics.”
It is feared a sharp upswing of Covid cases in South Africa’s Gauteng province — where the heavily mutated strain of the virus was first identified — could mean it has greater potential to escape prior immunity than other variants. The number of omicron cases “appears to be increasing” in almost all of South Africa’s provinces, the WHO reported.
The organization only labels Covid strains as variants of concern when they’re more transmissible, more virulent or more adept at eluding public health measures including vaccines and therapeutics.