A passenger (right) leaves on foot after disembarking from the Diamond Princess cruise ship (rear) at the Daikoku Pier Cruise Terminal in Yokohama, Japan, on Feb 19, 2020. (CHARLY TRIBALLEAU / AFP)

TOKYO - Hundreds of people began disembarking a cruise ship quarantined in Japan on Wednesday as criticism mounted of Japan’s handling of the sea-borne outbreak where the new coronarvirus appears to have run rife and infected more than 540 people.

The first group of about 500 passengers, mainly the elderly who have tested negative for the virus, started to get off the Diamond Princess cruise ship after finishing final checkups with doctors, Xinhua reports.

The first group of about 500 passengers, mainly the elderly who have tested negative for the virus, started to get off the ship after finishing final checkups with doctors

The ship, operated by Carnival Corp, was quarantined since arriving in Yokohama Feb 3 after a man, who disembarked in Hong Kong before it traveled to Japan, was diagnosed with the virus.

Coronavirus infections on the cruise ship rose to 621 people on Wednesday, as Japan’s health ministry said it had discovered 79 additional cases of the disease. 

Of the new cases, 68 showed no symptoms, it said.

According to the governement, nearly 3,000 people will disembark from the ship. A health ministry official said the entire process was expected to be completed by Friday.

Only passengers who test negative and do not show symptoms are being allowed to leave the ship. Those who have tested negative but were in cabins with infected people would remain on board for additional quarantine, Japanese officials said.

Passengers who have disembarked would be transported to Yokohama and other train stations in the area, and they would be allowed to go home by public transportation.

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The outbreak on the liner resulted in the biggest concentration of new coronavirus infections outside China despite more than two weeks of quarantine for its approximately 3,700 passengers and crew on board.

As questions swirled over how the virus spread so readily on the ship, Health Minister Katsunobu Kato defended Japan’s efforts.

“Unfortunately, cases of infection have emerged, but we have to the extent possible taken appropriate steps to prevent serious cases, including sending infected people to hospital,” Kato said in a report by state broadcaster NHK.

Passengers load suitcases into a car as they leave after disembarking from the Diamond Princess cruise ship, at the Daikoku Pier Cruise Terminal in Yokohama, Japan, on Feb 19, 2020. (CHARLY TRIBALLEAU / AFP)

The US Centers for Disease Control and Prevention (CDC) said Japan’s efforts might have slowed down the virus but were not enough.

“CDC’s assessment is that it (the quarantine) may not have been sufficient to prevent transmission among individuals on the ship,” it said in a statement.

QUESTIONS

Japan has repeatedly said its response to the outbreak on the ship has been appropriate.

CDC’s assessment is that it (the quarantine) may not have been sufficient to prevent transmission among individuals on the ship.

US Centers for Disease Control and Prevention

The United States has flown home more than 300 American evacuees from the ship and other countries are queuing up to collect their citizens, including Australians.

The United States, Australia, and other countries, are making their citizens spend 14 days in quarantine upon their return.

Asked why the Americans faced an additional two-week quarantine after returning home but Japanese leaving the ship did not, Chief Cabinet Secretary Yoshihide Suga said it was based on the advice of Japan’s National Institute of Infectious Diseases (NIID).

The NIID said that based on the experience of those who returned from Wuhan, the epicenter of the epidemic, on charter flights earlier this month, there should be no obstacle to using public transport and the like if people had shown no symptoms such as fever for 14 days and had tested negative for the virus during the period their health was under surveillance.

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A military personnel assists an elderly passenger after he disembarked from the Diamond Princess cruise ship, at the Daikoku Pier Cruise Terminal in Yokohama, Japan, on Feb 19, 2020. (CHARLY TRIBALLEAU / AFP)

With Japan just months away from hosting the 2020 Olympic Games, critics say the government’s response has seemed more concerned with managing public perception than the outbreak.

From the start, experts raised questions about quarantine on the ship. Passengers weren’t confined to their rooms until Feb 5. The day before, as officials screened them, onboard events continued, including dances, quiz games and an exercise class, one passenger said.

Besides those on the cruise liner and returnees brought home from China’s Wuhan city, the epicenter of the epidemic, about 60 cases of domestic infections have been confirmed in Japan, including 22 in Tokyo, according to NHK.

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Amid worries about a contracting economy, the spread of the virus has prompted Tokyo to curb the size of public gatherings and some companies are telling employees to work from home.

The spread of the virus has also raised concerns about the outlook for the Tokyo 2020 Olympics, set to start on July 24, although organizers have said there are no plans to cancel the Summer Games.

US President Donald Trump said on Tuesday that he was considering visiting Japan for the Games at the invitation of Prime Minister Shinzo Abe.

With Xinhua inputs