A scramble intensified on Monday to trace around 1,200 passengers from US cruise liner Westerdam, allowed to disembark in Cambodia, after one traveller was later diagnosed with the deadly coronavirus — the American woman only made it as far as the Kuala Lumpur Airport in Malaysia where she was stopped at the thermal scanner; she later tested positive.

Meanwhile, 14 passengers, all American, who were evacuated from another cruise ship, Diamond Princess, this one in Japan, and initially believed to be free of the virus, tested positive shortly before their chartered flight was to take off for the US. They were flown out — after a section of the aircraft was made into a contained space for them — along with the other evacuees.

Outside China, the Diamond Princess has had the largest number of cases of the COVID-19 illness caused by the virus that emerged in China late last year.

Both incidents raised fresh concerns about the quality of screening ahead of evacuation or release of people who have had the chance of being exposed to the highly contagious virus, which originated in China and has killed around 1800 people, almost all in China, and infected tens of thousands across 26 countries (but, again, mostly in China).

On Monday, about 70 Wuhan evacuees were discharged from the Indo-Tibetan Border Police’s quarantine facility on the outskirts of Delhi, and by Tuesday evening all 406 people under quarantine at the ITBP facility are expected to leave for their respective homes. None of them were infected, the health ministry said.

However, the Westerdam issue has raised fears that potentially tens of infected passengers may now be scattered across the world without full health checks — as Cambodia on Monday afternoon treated a few dozen of the passengers to bus tours around the capital Phnom Penh.

Passenger Christina Kerby, whose droll tweets as the Westerdam was bounced across ports drew widespread attention, admitted she was “surprised” to be allowed on a tour of the Cambodian capital before being given the complete all-clear from the virus. “I have young kids back home (in the US) and wouldn’t want to risk infecting them or anyone around me if I am carrying the virus,” she told AFP.

The Westerdam was at sea for two weeks during which it was barred from Japan, Guam, the Philippines, Taiwan, and Thailand over fears it could be carrying the virus. On Thursday Cambodia, a staunch ally of Beijing, allowed the ship to dock at Sihanoukville. It was met by the kingdom’s bombastic premier, Hun Sen, who hugged disembarking passengers as he swiftly latched on to the Westerdam’s PR potential for a nation more often in the spotlight for human rights abuses. His stance won applause from US President Donald Trump. But three days later one Westerdam passenger, an 83-year-old American, was stopped on arrival in Malaysia and later diagnosed with the coronavirus. On Monday, Malaysia said over 130 other passengers who also took the flight with the sick American women left for the US, Europe and Australia and Hong Kong.

Thailand, a flight hub already used by scores of the Westerdam passengers, on Monday mulled a ban on transit by cruise goers, as the region played catch up to the risks posed by the boat. “Passengers on ship are at risk and travel by airplane will cause risk to other passengers,” health minister Anutin Charnvirakul said Monday. Cruise operator Holland America is working with national health authorities “to investigate and follow up with individuals who may have come in contact with the guest”, chief medical officer Dr Grant Tarling said late Sunday.

Another 233 passengers and 747 crew remain on the Westerdam, which is still docked at Sihanoukville.

Authorities have been allowing them to leave the vessel in groups based on their flight bookings but those on board told AFP they are now not permitted to disembark.A Sihanoukville spokesman said Monday health samples are being collected from all onboard the Westerdam “in order to be clear”, adding that passengers will not go off-ship until the tests are completed.

China’s foreign minister Wang Yi will meet South-east Asian counterparts in late Laos this week to discuss the unprecedented health crisis, which has battered manufacturing and tourism across the region and led to an array of travel restrictions.

In Tokyo, Japanese health ministry officials confirmed on Monday that 99 more people were infected by the new virus aboard the quarantined cruise ship Diamond Princess, bringing the total to 454. The 14 Americans are part of the 99.

The ministry has been carrying out tests on passengers and crew on the ship, docked in Yokohama, a port city near Tokyo.

The 14-day quarantine for those on the ship was due to end Wednesday. The ministry said it now has tested 1,723 people on the Diamond Princess. The ship had about 3,700 passengers and crew.

Two chartered planes flew 340 Americans who were aboard the vessel out of Japan. About 380 Americans had been on the ship. The State Department announced later that 14 of the evacuees were confirmed to have the virus in tests given before they boarded the planes.

They were taken to the US because they did not have symptoms and were being isolated from other passengers on the planes, it said.

Australia, Canada, Hong Kong and Italy were planning similar flights for their citizens.