LOS ANGELES, United States — Passengers trapped aboard a US cruise ship stranded by a coronavirus outbreak spoke of their growing anxiety Saturday as the vessel idled off the coast of San Francisco with little news on when they will be allowed to disembark.

One of the holidaymakers told AFP the captain of the Grand Princess announced early Saturday that there was “still no word on when or where we will be docking”.

Carolyn Wright, a professional photographer travelling with a friend, said the captain earlier said it was unlikely the ship would dock on Saturday.

She said a critically ill passenger was evacuated overnight by the coast guard and all guests remain confined to their cabins.

Authorities have said 21 people on board the ship languishing 50 miles off the coast of San Francisco, tested positive for the new coronavirus — 19 crew members and two passengers.

Vice President Mike Pence, who has been put in charge of the US government’s response to the COVID-19 outbreak, said Friday the ship would be brought to a non-commercial dock over the weekend and all 3,533 passengers and crew would be tested.

“We will be testing everyone on the ship and quarantining as necessary,” Pence said. “But with regard to the 1,100-member crew, we anticipate that they will be quarantined on the ship.”

The boat had been scheduled to dock in San Francisco Saturday after a 14-day cruise but was held off the coast after it emerged that two passengers who had been on a previous voyage had contracted the virus. One of them later died.

Wright said although there didn’t seem to be panic among passengers, there was growing concern and frustration.

“So far we are both fine and we are really hoping to stay that way,” she told AFP, speaking about her travelling companion.

“My friend has COPD (pulmonary disease) and she is extremely concerned about the virus.”

She said passengers — who have been confined to their cabins since Thursday — at one point on Friday were told they would be allowed out for some fresh air, but the idea was nixed by health authorities.

Another passenger, quoted by the San Francisco Chronicle, said he and his wife had also received little information about the outbreak from crew members.

Daniel Healy, 56, told the paper he ran out of diabetes medication on Friday, and was refused “point blank” when he asked to speak to a medical professional.

Health officials sounded the alarm over the cruise ship after several passengers who were on the previous voyage and remained on the vessel for its next trip to Hawaii developed flu-like symptoms.

The company said gloves and face masks were delivered to the Grand Princess by helicopter late Friday.

More than 200 people have contracted the virus in the United States, and 19 have died, 16 of them in the west coast state of Washington.

Worldwide, the virus has killed over 3,500 people and infected more than 100,000 across 92 nations, according to the latest count by AFP.