The Japanese government said Wednesday it will tighten border controls for visitors from some countries, including Myanmar and Iran, to prevent the spread of highly contagious new variants of the coronavirus.

In a set of changes to border control measures taking effect Saturday, those arriving from Myanmar will be asked to stay in designated facilities for six days after arrival and take additional virus tests on the third and sixth days.

Travelers from Iran, Oman, the U.S. states of Oklahoma and Missouri, and the Russian oblasts of Ivanovo and Vladimir will also be required to observe a three-day quarantine in designated facilities and be subject to more coronavirus testing the third day.

A six-day quarantine will now be requested for visitors from Pakistan, reduced from 10 days, and they must retake tests on the third and sixth days.

Travelers from Uganda will be asked to observe a three-day quarantine, down from six days.

Those from Egypt, Sweden, and the U.S. state of New Mexico will no longer have to stay in designated facilities if their test results upon arrival are negative but will still be requested to undergo self-isolation for 14 days after entering Japan.

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