As of the time of writing, March 8th 2021, the Government of Japan has declared a State of Emergency for certain parts of the country, accompanied by a set of new border restrictions.
At the moment, persons with a valid Residence Status in Japan are eligible to re-enter the country. That being said, persons entering from overseas are bound to honor the following in order to be permitted re-entry.
It must be noted, however, that criteria for entry into Japan, border restrictions and so on are different for citizens of each country/region and are changing on a daily basis (whether or not your country/region has been recognized to have community transmission of coronavirus variants of concern or domestic confirmation of new variants, etc.). Always make sure to check the most up-to-date information on the homepage of your local Japanese diplomatic mission.
[About Border Restrictions]
・Ministry of Foreign Affairs: https://www.mofa.go.jp/ca/fna/page4e_001053.html#section2
[Entry Procedures: Key Points] *the following is subject to change at the discretion of the Government of Japan.
・Submit a Pledge Form to the health inspector upon entering the country (You do not need to apply through the university to complete this Pledge Form)
・Take your temperature daily during the 14 days prior to your travel to Japan (further, if any irregularities are registered you must cancel your travel plans)
・Acquire a Covid-19 negative test result from a test taken within 72 hours of the scheduled departure time of your flight into Japan
・Download LINE and add the designated health system account to your friend list, then enter your health status information into the system each day, for the first 14 days after your arrival in Japan
・Download the Ministry of Health, Labour and Welfare’s Covid-19 contact tracing app, a register an account, and leave the app running for the first 14 days after your arrival in Japan
・Record your GPA location data via a map app for the first 14 days after your arrival in Japan
・Use of public transit in Japan is forbidden during the first 14 days after your arrival in Japan
・For the first 14 days after your arrival in Japan you must reside at your home or self-isolation stay hotel, monitor your health status, and report your health status as required, such as via the LINE app described above