The World Health Organization has said that the new strain of the coronavirus omicron poses an "extremely high" global risk, but clinical data on its severity remains limited.
"The overall risk associated with omicron remains very high. Firstly, in certain cases it evades vaccine protection. Secondly, the omicron strain is characterized by a high transmission rate, which can lead to further spikes with serious consequences," the WHO said.
Although preliminary data suggest that omicron may be less dangerous than the delta strain - all cases reported in the European region were mild or asymptomatic - it remains unclear to what extent omicron may be inherently less virulent.
"More data is needed to understand the severity profile," the WHO said.