are now begging to be allowed off the ship after owner Holland America Line said in a Facebook post that four "older guests" have died.
Officials have not identified a cause of death for any of the four.
Neil Bedford told Associated Press his parents Jim and Chris Bedford are stuck on the ship and desperate to get back home to Bradford.
'NEVER GOOD NEWS' He said: "Meals are delivered to their rooms three times during the day.
"The captain is making announcements once a day, but everyone seems to be getting frustrated as it's constantly bad news.
"They're just growing increasingly concerned with what will happen to them."
He said the couple, both of whom are in their 60s, are "terrified" of being trapped onboard the ship .
Hayley Pillai Johnson, a medical student at Cambridge University, has taken to Twitter to ask what will happen to her grandfather and his wife.
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"They're scared now that they've heard of the four deaths," Hayley said.
"We're worried sick about them."
Canadian passengers Chris and Anna Joiner took a picture of themselves holding a sign reading: "Help us."
The picture shows the couple wearing face masks and confined to a cabin.
The Zaandam, which has 1,243 guests and 586 staff aboard, has now been denied passage through the Panama Canal.
It has four doctors and four nurses onboard and is receiving medical supplies from another Holland America ship.
BODIES TO STAY ONBOARD In a statement, the company said it hopes to get healthy passengers onto the second ship.
Bodies of those who have died will stay on the Zaandam until the liner arrives at its final destination.
Panama has refused to allow either of the Holland America ships to dock.
The country has 786 coronavirus cases, and 14 people have died .
The Zaandam left Buenos Aires, Argentina, on March 7. It was aiming to reach Fort Lauderdale in Florida after being denied permission to dock at its original destination of San Antonio, Chile, a week ago.
No one has left the ship since March 14, the company says.
In February, a British man became the first UK citizen to die from coronavirus after being infected on the Diamond Princess cruise ship in Japan.
He was the sixth passenger to die.
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