A variant of the coronavirus was detected in Japan among four tourists from Brazil's Amazonas state, the Japan Times reported Monday quoting an update from government health officials.
Many regional governments in Japan requested a state of emergency to contain a wave of cases.
Safety measures authorized by Japan Prime Minister Yoshihide Suga were enforced in Tokyo and the surrounding Kanagawa, Saitama and Chiba regions last week. These see restaurants and nightclubs closing from 8 p.m. for at least 30 days.
"At the moment, there's no evidence that shows the new variant found in those from Brazil is high in infectiousness," Takaji Wakita, director of the National Institute of Infectious Diseases, said in remarks during a health ministry briefing.
Of the four travelers, a man in his 40s was taken to hospital after breathing difficulties, a woman in her 30s said she had headaches and sore throat and a male teenager developed a fever.
Studies continue into the effectiveness of vaccines against the new variant - which has different characteristics compared with an initially discovered highly infectious variant in South Africa and Europe, a health ministry official said. The Japan variant is the latest showing the virus is evolving even as international vaccination efforts ramp up.
Worldwide, COVID-19 cases have passed 90 million with fatalities of more than 1.9 million. More than 24 million people have so far been given vaccine shots. Cumulative cases of COVID-19 in Japan are around 289,000 with 4,061 deaths, according to state broadcaster NHK.
Japan is set to host the 2021 Olympics and Paralympics this summer after being forced to postpone them one year as a result of the pandemic.
