"We have very effective vaccines that have proven to be effective against all variants so far, in terms of severity of disease and hospitalisation, and there is no reason to think that this would not be the case with Omicron," said WHO emergency manager.
A World Health Organization senior scientist said Tuesday that "there is no doubt" about the efficacy of current vaccines to protect Omicron-infected patients from severe forms of COVID-19.
The current vaccines are effective against Omicron, which does not appear to be more dangerous than Delta, the variant that circulates most in the world, senior scientists from the WHO and the White House have said.
This comes as Poland and several other countries across Central and Eastern Europe battle a massive surge of new infections and deaths fueled by the transmissible Delta variant, and amid fears the current vaccines will be less effective against the new Omicron variant.
"We have very effective vaccines that have proven to be effective against all variants so far, in terms of severity of disease and hospitalisation, and there is no reason to think that this would not be the case with Omicron," said Dr Michal Ryan, executive director of the WHO Health Emergencies Programme.
However, Ryan acknowledged that vaccines might be less effective against Omicron, which is characterised by a very high number of mutations.
But "it is highly unlikely" that the variant could escape vaccine protection entirely.
The WHO emergency manager stressed that studies of the variant -- detected only on November 24 by the South African authorities and which was since spotted in dozens of countries -- were still in their infancy.
"The general pattern we are seeing so far shows no increase in severity. In fact, some places in southern Africa are reporting milder symptoms," Ryan insisted.
The appearance of this new variant has caused wide panic in Europe, which is already experiencing a fifth wave of COVID-19 cases caused by the Delta variant.
The WHO has confirmed over 400 infections across the continent since the first case was discovered.
Several countries around the world have announced border closures, including for South Africans.
The move angered Pretoria, which denounces an unjustified ostracisation.
The Austrian government turned to mandatory vaccination for all of its citizens, while Norway announced on Tuesday that it was strengthening health measures to combat an outbreak of coronavirus, including limiting the number of people at home events, including Christmas parties.
However, the WHO has advised governments to only use mandatory vaccination as a last resort in fighting the pandemic.
On Wednesday, BioNTech's Chief Medical Officer, Özlem Türeci, said that the coronavirus vaccine developed jointly by BioNTech and Pfizer neutralises the Omicron variant of the virus after three doses.
A laboratory study by its makers found that "three doses of our vaccine neutralise the Omicron variant", but warned that "two doses show significantly reduce neutralization of this new variant."
Pfizer and BioNTech also said that an Omicron-specific version of the anti-coronavirus vaccine, currently in development by BioNTech, would be available by March.
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