Over the next five days, Japan faces the daunting task of testing thousands of passengers aboard a quarantined cruise ship, evacuating them and transporting those who test positive for the coronavirus — or who may have come in contact with someone who has — to medical facilities on shore.

With the health ministry yet to announce a plan to address these issues or to extend the quarantine, which is scheduled to end Wednesday, the task of getting everyone off the Diamond Princess by the deadline grows increasingly improbable.

The whole situation is like “a game with no end in sight,” said Koji Wada, a professor of public health at the International University of Health and Welfare.

“As the time limit gets closer, the question now is whether it’s possible to send everyone home in time,” he said. “It’s entirely possible that not all passengers will be evacuated by the end of the quarantine period.”

So far, those infected with COVID-19 start to show symptoms anywhere between two and 14 days after contracting the virus. Thus a two-week quarantine was placed upon the cruise ship, which was carrying more than 3,700 passengers and crew, after an 80-year-old man who left the ship in Hong Kong tested positive for the virus.

But if secondary infections are occurring on the ship, as many experts suspect, the 14-day quarantine — which began on Feb. 5 when the Diamond Princess arrived at Yokohama Bay — will prove meaningless.

Still, the health ministry has not officially changed its plan to end the quarantine on Feb. 19 nor explained to the public what strategies it will take to contain the outbreak after the deadline.