Japan on Wednesday confirmed its fourth case of infection by the Omicron variant of the novel coronavirus, the health ministry said.
A man in his 50s with a history of travel to Nigeria tested positive upon arrival at Narita airport near Tokyo on Saturday, according to the Ministry of Health, Labor and Welfare.
The other 103 passengers on the same flight have been identified, and their health conditions will be monitored, the ministry said. The man received his first and second doses of Pfizer Inc.'s COVID-19 vaccine in October, it said.
Japan confirmed its first case of the Omicron variant on Nov. 30. So far, all four cases have been detected at airports as people arriving from abroad were tested for coronavirus infection.