Mar 26, 2020, 6:55 PM (17 hours ago)

I hear things are stricter in other countries, so I am just capturing this as a datapoint; I got this in an email from U.S. Embassy Tokyo

Japan’s Enhanced Screening and Quarantine Measures for Travelers
from the United States: The Government of Japan has implemented
enhanced screening and quarantine measures to reduce the spread of
COVID-19.  Effective March 26, all travelers arriving from the
United States, including Japanese citizens, will be required to
self-quarantine for a period of 14 days at a designated facility,
and to avoid using any public transportation, including taxis,
trains, and buses, until after the 14-day period.  Transiting on a
domestic flight within Japan is also considered public
transportation, so you will not be allowed to fly to your onward
destination in Japan until completing the 14-day self-quarantine.
The self-quarantine location may be your residence if you live in
Japan or a hotel, but the Japanese government reserves the right
to “designate” the location of your self-quarantine.  Travelers
should be prepared for travel restrictions to be put into effect
with little or no advance notice.