TOKYO: Japan has confirmed its first case of Omicron variant of the coronavirus, Kyodo News reported citing a government source.

A man in his 30s was found to be infected with the heavily mutated strain after arriving from Namibia at Narita airport near Tokyo on Sunday, according to the source. The WHO, on November 27, named the new COVID-19 variant B.1.1.529, which has been detected in South Africa, as ‘Omicron’.

This variant has a large number of mutations, some of which are concerning. The number of cases of this variant appears to be increasing in almost all provinces in South Africa.

The World Health Organization has warned the Omicron variant, which has already been confirmed in Europe, Canada, Israel and Hong Kong, may be more transmissible or evade immunity from previous infections and vaccines.

Concerns over the variant have prompted a number of countries to tighten travel restrictions, with Japan closing its borders to new arrivals of foreigners from Tuesday and requiring citizens and foreigners with resident status returning from high-risk areas to quarantine up to 10 days in a government-designated facility.