Ten people aboard a cruise ship anchored off the coast of Yokohama, Japan, tested positive for the new coronavirus, Japanese media reported Tuesday. The news comes as the number of reported infections outside China continues to grow.

The roughly 3,500 passengers and crew aboard the British-flagged ship, the Diamond Princess, have been quarantined for more than a day after a traveler from Hong Kong was diagnosed with the new coronavirus.

All the infected passengers were in their 50s or older, with some in their 80s, Japan’s health and labor minister said, according to the news agency Jiji. Three were said to be Japanese nationals.

More than 270 people are being tested, said Katsunobu Kato, Japan’s minister of health, labor and welfare, the Nikkei Asian Review reported.

“We ask passengers to remain in the ship for at most 14 days,” Kato said. “We would like to take thorough measures.”

Those testing positive are being brought to medical institutions on land, he added.

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The original infected passenger embarked in Yokohama on Jan. 20 and disembarked in Hong Kong on Jan. 25, Princess Cruises said in a statement Tuesday. During that time, he did not visit the ship’s medical center or report any symptoms, according to the company. Six days after leaving, he tested positive for the coronavirus in a Hong Kong hospital, Princess Cruises said.



People are transferred from the Diamond Princess cruise ship to a patrol ship. (Kyodo News/Reuters)

Japanese health officials began screening passengers Monday night, focusing on those showing symptoms and others who had contact with potentially infected people, according to NHK, Japan’s public broadcasting network.

“The safety, security and well-being of all guests and crew is our absolute priority,” Princess Cruises said. “The review of the arriving guests and crew, by Japanese health authorities, is standard practice after a guest tested positive for coronavirus and we are working closely with the local authorities to provide detailed records to facilitate their review.”

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Officials from the World Health Organization said nine countries outside China have confirmed 27 instances of human-to-human transmission, while cases continued to soar in China, where the outbreak began in Wuhan, a city of 11 million.

The most common symptoms are fever and cough, officials said.

On the Diamond Princess, passengers and crew remained on lockdown aboard the ship, according to the British channel ITV. Most people self-quarantined in their rooms while they awaited medical checks, passengers told the channel.

One passenger, David Abel, said he had to cancel a Monday night flight back to Oxfordshire, England, after the ship was denied permission to dock.

“The ship is like a ghost town,” he told ITV. “It’s really weird.”

Carolyn Y. Johnson and Lena H. Sun contributed to this report.

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