TOKYO (UPDATE) - Japan has confirmed its first cases of the new, potentially more transmissible coronavirus variant spreading in Britain, the health ministry said Friday.

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The five -- four males and one female and all under age 70 -- are now staying at hotels provided by authorities after airport quarantine confirmed their infections following their arrival from Britain.

None of them had close contact with others since returning to Japan, the ministry said. Four of them are asymptomatic.

At least one child under the age of 10 is among the infected. The ministry did not disclose other details of the five.

Two of them arrived at Haneda airport in Tokyo while the others landed at Kansai airport in Osaka Prefecture, western Japan, it said.

"We will do everything we can to eliminate the chances of (the new strain) spreading in Japan," health minister Norihisa Tamura said.

Takaji Wakita, head of the National Institute of Infectious Diseases, told a press conference that as the infections were detected at the airport, he believes the mutant virus "is not spreading in Japan."

Japan on Thursday imposed a temporary ban on new arrivals of foreign nationals from Britain coming for purposes such as business or study, but existing foreign residents and Japanese nationals have still been allowed to enter.

Foreign residents of Japan, who already have to undergo COVID-19 testing as a condition of reentry from most countries, including Britain, are asked to download a tracing app for COVID-19 infections and retain their location data after entering Japan.

Japanese nationals arriving from Britain from Sunday will be required to take virus tests within 72 hours before departure and submit the results upon arrival.

The move came as countries worldwide impose restrictions on travel from Britain following the spread of the strain, which is believed to have caused a spike in infections in London and southeast England.

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Tourist visits from Britain are already barred.

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British health officials have said the new strain, which was first detected in September, could be up to 70 percent more transmissible but that there was no evidence of it being deadlier or reducing the effectiveness of vaccines.

Cases have already been confirmed in Australia, Denmark, Italy, the Netherlands and South Africa, according to media reports.

==Kyodo

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