On Thursday, almost 4,000 passengers and crew remained trapped on the World Dream at Kai Tak Cruise Terminal after it was turned away from Taiwan following the discovery it had carried the infected group during a January cruise between Hong Kong and Vietnam.

The 1,800 passengers, including 1,600 from Hong Kong and others from Britain, Australia, Canada, Taiwan, Macau and elsewhere, together with most of the other 1,800 crew members, were all still on the ship, which left the city on Sunday for its latest voyage, and was boarded by Department of Health officials on its return on Wednesday morning.

A 66-year-old man stranded on the ship said passengers had been told to stay in their rooms on Thursday, so government officers could check their body temperatures.

But he said no announcement had been made on whether they could go home after the check, or if they would be quarantined somewhere.

He said he wanted to go home if the checks found he was healthy, and said forcing healthy passengers to be isolated on the cruise for 14 days, as some district councillors have suggested, would expose them to the threat of becoming infected.

Some passengers on board, especially the elderly, were already running out of medication, he said, and added that he had no more pills to control his cholesterol levels. But there were still adequate supplies of food and passengers could ask for masks.

“The cruise is a confined space. It’s not ideal if we are asked to be isolated here for longer,” he said. “Many of the passengers are 50 years old or older. Some of them need drugs to control their blood pressure and they are running out of them.”

Busker Rex Lui, 56, said he joined the cruise on his own, as he could book it for less than HK$5,000 (US$640).

“Hong Kong has too many grievances, so I thought of going to Taiwan. Although Taiwan was also hit by the epidemic, it was not that serious,” Lui said.

He said he felt quite sad knowing he could not get off the vessel in Hong Kong.

“But I can’t complain. It’s my choice. The government’s arrangements are to safeguard the health of the residents,” he said.

He said the captain on Thursday told them each passenger could get a free mask daily, but Lui said he only brought enough clothes for five to six days, so he would have to wash them in the room later.

Meanwhile, project manager Michelle, 27, who was on a family trip, was worried, as she was scheduled to return to Britain next week, and was not sure if she would be quarantined.

“It’s ridiculous that the government is making a fuss now, but the company is to take the blame as well,” she said, after learning the cruise line had operated three other trips.

“If the cases were suspected after the trip, they should have notified the passengers so we could consider the risk of our trip, even if it’s the fourth one.”

But she said staff had been cleaning the vessel throughout the journey and everyone had been wearing masks, so she was “less worried that I will catch the virus”.

Dream Cruises, the ship’s operator, confirmed to the Post it had carried three groups of travellers between the eight infected passengers’ disembarkation and the ship’s departure for Taiwan on February 2, carrying 3,600 passengers and crew.

It said it had not deliberately concealed information about the trips.

“The information we disclosed [on Wednesday] mainly focused on the timeline of the [current] incident, and a series of things happened after we received the authorities’ notification [about the infections] on February 3,” it said.

“It was not that we intentionally did not mention the trips.”

Officials spent Wednesday conducting health checks on the passengers and crew of World Dream, and have said they will only be allowed to leave the vessel when they give the all-clear.

As of Wednesday evening, 33 crew members claimed to have developed symptoms of an upper respiratory tract infection. All tested negative for the coronavirus. But the cruise company said on Thursday evening a Nepali crew member developed fever and was sent to hospital.

The Centre for Health Protection said one passenger had fever and had been sent to hospital by 8pm, while eight others reported mild respiratory symptoms.

On January 19, the cruise first sailed from Hong Kong to Nansha port in Guangzhou, before going to Vietnam, carrying more than 4,000 passengers at the time. It returned to Guangzhou and Hong Kong on January 24, when the eight infected passengers disembarked.

The cruise company was first informed by Chinese authorities on Monday that three mainland Chinese passengers on the trip were found to be infected with the virus. Five more cases were later confirmed.

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When the company was informed of the sick travellers, the same cruise was already carrying 3,600 passengers and crew from Hong Kong to Kaohsiung, Taiwan.

On Tuesday, the Taiwanese government refused World Dream permission to dock in Kaohsiung, although it had already docked briefly in Keelung, where those on board were allowed to disembark.

In outlining the other three trips the vessel had taken, the cruise operator said on the day the eight infected passengers left, the ship returned to Hong Kong and sailed to the South China Sea on a “weekend escape”, returning two days later on January 26.

That same day, the vessel again left Hong Kong and sailed to Manila, in the Philippines, where passengers were allowed to land. It returned to Hong Kong on January 31.

The third trip, starting on the same day, saw the cruise return to the South China Sea and arrive back in Hong Kong on February 2.

On Thursday, Dream Cruises said it could not tell if the same crew members worked all of the trips, including those with the infected passengers. Nor could it confirm the number of travellers and crew members on the unreported voyages.

It said it had only managed to seal the cabins in which the infected passengers stayed on Tuesday, the day after it was contacted by Chinese authorities.

The cruise line also said there were sufficient supplies for all passengers and crew members, including face masks.

“According to our records, there are nine infants under the age of two on board and our crew has been in contact with their accompanying family members to assist in any way to provide supplies,” it said.

“We have also aided in the delivery of required medication for several passengers.”

Hong Kong’s health authorities said on Thursday about 5,000 people had travelled on the cruise and disembarked in Hong Kong after the eight mainlanders with the coronavirus travelled on it.

Among them, 206 passengers travelled with the eight infected mainlanders and thus had a higher risk of contracting the virus, said Chuang Shuk-kwan, head of the communicable diseases branch of the Centre for Health Protection.

She appealed to the estimated 5,000 travellers to contact the government.

Dream Cruises said most of the 206 passengers had made their bookings through travel agencies, and had already asked the agencies for the passengers’ contact numbers. That information would be passed to the government once they have it, the cruise line said.

Civic Party lawmaker and urologist Kwok Ka-ki, meanwhile, said passengers on the other trips could also carry the virus, and he urged the government to track down those people to prevent a community outbreak.

“Those people are as likely as the travellers currently stranded on the cruise to have the virus,” Kwok said. “They have returned to the community and it is possible that they have the virus but they have not shown the symptoms yet.”

The virus is believed to have a 14-day incubation period.