Concerns mount after woman who left 'virus-free' cruise ship in Cambodia tests positive

An 83-year-old American passenger from a cruise ship that docked in Cambodia after being shunned by other countries has tested positive for the new coronavirus in Malaysia.

Passengers wave from the MS Westerdam cruise ship at a seaport in Preah Sihanouk province, Cambodia, 14 February 2020. Source: AAP

Malaysia insisted Sunday it had correctly diagnosed coronavirus in an elderly American woman from the Westerdam cruise ship despite all passengers having been given a clean bill of health when they disembarked in Cambodia.

The vessel was at sea for two weeks and barred from Japan, Guam, the Philippines, Taiwan and Thailand over fears it might be carrying the virus which originated in China and has killed more than 1,600 people.

Cambodia - a staunch ally of Beijing - allowed the ship to dock Thursday in Sihanoukville, administering health tests before passengers disembarked in waves for homeward-bound flights.

But jubilation dimmed late Saturday, as one of the passengers was stopped by authorities in Malaysia when she was detected with a fever and was later diagnosed with the virus.

Passengers leave the cruise ship docked in Cambodia. Source: AAP

Now fears are mounting that more of the 2,200 passengers and crew who disembarked may have been infected.

Cambodia urged Kuala Lumpur on Sunday to "double-check" the diagnosis, but Malaysian deputy prime minister Wan Azizah Wan Ismail said the 83-year-old American woman had already been tested twice.

"Our protocol is actually world-class... it's a positive," she told a press conference.

She said the US embassy had chartered four Malaysian Airlines planes to fly some of Westerdam's passengers to Kuala Lumpur, but later a government statement officially corrected her account, saying it was the cruise ship operators who had hired the aircraft.

After the discovery of the infected woman on the first plane carrying 143 passengers, the other flights were cancelled.

Onboard the Westerdam - where more than 200 passengers remain along with 747 crew members - the mood has turned "sombre", said Lorraine Oliveira, who lives in Britain.

"Guests are very anxious on board since finding out someone tested positive," she told AFP.

"We were (so) close to getting home and now we're back in limbo."

A bus waits for passengers to disembark from the Westerdam cruise ship at the port of Sihanoukville in Cambodia. Source: AAP

Cambodia's decision to allow the Westerdam to berth was lauded US President Donald Trump, who called the country "beautiful" on Twitter, while US ambassador Patrick Murphy boarded the ship to greet its American passengers.