Four passengers have died on a cruise ship that has been unable to find a port to disembark, operator Holland America Line said Friday. On Friday afternoon, the ship was off the coast of Panama with a plan to head to Fort Lauderdale, Fla.

Passengers and crew aboard the Zaandam cruise ship started reporting flu-like symptoms on March 22, when guests were told to stay in their rooms. Two people on the ship have tested positive so far for covid-19, the disease caused by the novel coronavirus, after an unspecified number were tested. According to the company, 138 people on the ship were sick as of early Friday — 53 guests and 85 crew.

It wasn’t yet clear what the four passengers died of; the ship only got access to coronavirus tests within the last couple days. There are 1,829 people on board, 586 of whom are crew members.

[Coronavirus live updates]

Passengers who are not ill will be transferred to another of the company’s ships, the Rotterdam, where they will have to stay in their staterooms. A time frame was not available, but the first to move to the other ship will be those who are older than 70 and passengers who are in inside staterooms without access to the outdoors.

Those who are showing symptoms, or their close contacts, will stay on the Zaandam with all crew. There are four doctors and four nurses on the ship; the Rotterdam has two doctors and four nurses.

“Crew have been amazing,” passenger David Haycox, a retiree who lives in Brooke, England, said in an email. “What incredible circumstances to deal with.”

The Rotterdam met up with the Zaandam on Thursday night while both were at anchor off Panama to deliver medical supplies and bring more medical staff to the ship.

Like most of the cruise industry, Holland America, which is owned by Carnival Corp., suspended operations of its global fleet on March 13 for a month but still had to get its ships back to port. Zaandam’s voyage left Buenos Aires on March 7; the company planned for passengers to disembark on March 16 in Punta Arenas, Chile, but the Chilean government would not allow anyone off.

“The South American countries that are very happy to take tourist income wash their hands (pun intended), at the first opportunity,” Haycox said in his email.

The U.S. State Department and Centers for Disease Control and Prevention warned Americans, particularly those with underlying health conditions, to avoid cruise travel on March 8.

Zaandam was one of several ships still at sea Friday trying to make their way back to ports that would allow passengers to disembark. As of late Wednesday, there were about 15 ships from operators that belong to the Cruise Lines International Association, according to the group. Most did not report any sick passengers on board.

The last time anyone had been off the Zaandam was March 14 in Punta Arenas. Passengers have been confined to their rooms and getting food delivered since Sunday, when 42 people reported to the medical center with flu-like symptoms. By Tuesday, that number had risen to 77.

Holland America is working to get permission for the Zaandam to sail through the Panama Canal and head to Fort Lauderdale, but it’s still not clear whether they will be allowed to dock there. The Associated Press reported that Panama had denied the request to use the canal, but Holland America said the company was still working with authorities there on approval.

“That’s probably the most frustrating thing is the not knowing, the uncertainty,” said Kathy Leighton Carton, of St. Cloud, Minn., on board with her husband, Andy Vinson. They managed to see penguins in the Falkland Islands and Chile, and go on a couple of wine tours before the World Health Organization declared a pandemic and ports started shutting down to cruise traffic. But she said if they’d known how rapidly the disease would spread after they left home on March 4, they would never have gotten on the ship.

Already worried by the uncertainty around the ship’s plans and news of sick passengers, family members of those on board were shaken by Friday’s developments.

Hayley Johnson, 24, from Oxford, England, said her grandparents were on the ship; because her grandmother has a cough, she said, they will not be allowed to leave the Zaandam for the Rotterdam.

“There is no clear plan … how to manage this, and the uncertainty is making us all the more scared,” she said in an email. “In light of the four deaths already, Holland America need to get everyone off this ship and to shore safely, as a humanitarian act if nothing else.”

Suzanne Termaat, a consultant in Guaynabo, Puerto Rico, said her dad and stepmom, Charles Borg and Alyse Danis, had been glad to be in the relative bubble of the ship before anyone got sick. The couple — he is 80 and she’s 82 — live in San Francisco, and Termaat hopes they’ll be among the first to transfer to the Rotterdam.

“My brothers and I were saying, ‘Stay on the ship for a month or two months or three months, we don’t mind,” said Termaat, 52. "You’ll be healthier there as long as your ship is healthy."

The sentiment is different now, she said: “I think they just really, really want off.”

Read more:

A cruise ship is still trying to get passengers to port. Now 42 people onboard are sick.

Cruise ships are scrambling to find open ports for passengers stuck in the coronavirus shutdown

All major cruise lines halt sailings temporarily in response to coronavirus