The cruise ship had already been through a quarantine procedure on Saturday at a port in Naha in Japan’s southernmost prefecture of Okinawa, and quarantine officials had issued certificates allowing passengers and crew to land, Suga said.
A health ministry official said no-one aboard at that time showed any symptoms, and the case of the man who disembarked in Hong Kong was not known at that time.
After his case emerged, a second quarantine was organized.
Quarantine officials are now checking the condition of everyone on board and testing those with symptoms of illness for the new coronavirus, as well as other infectious diseases, including malaria and Dengue fever, a second health ministry official told AFP.
Health Minister Katsunobu Kato told parliament that tests for the virus would be administered to three groups: those with symptoms, those who got off in Hong Kong, and those who had close contact with the infected passenger.
Until the results are in “everyone on board… will stay there”. he said.
The decision on whether to allow the vessel to dock at Yokohama port and let passengers land on Japanese soil “will be made at the quarantine station,” taking into consideration the WHO’s estimate of a 10-day incubation period, Suga said.