The WHO says it is not yet clear whether Omicron is more transmissible than other Covid variants, including Delta, though its discovery has coincided with an uptick in cases in South Africa.
The global health agency said it is working with researchers across the world to establish whether the new “variant of concern” causes “more severe disease compared to infections with other variants”.
Meanwhile, secondary school students across England have been told they must once again wear face coverings in communal areas, as the government attempts to contain the spread of the variant.
Under the new guidance – which comes into force on Monday – all staff, visitors and pupils in Year 7 or above are “strongly advised” to wear a face covering, unless they are exempt. The rule covers all education establishments including universities, as well as childcare settings such as early years care.
It comes after a third Omicron case was confirmed in the UK, involving a traveller who visited Westminster but has since left the country.
It came after Sajid Javid admitted on Sunday that air passengers from South Africa were not tested on arrival into the UK on Friday – despite fears they could be carrying the new variant.
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