• Four passengers have died onboard Holland America's MS Zaandam, according to leaked audio from a sister ship sent to rescue stranded passengers.
  • The deaths come about as medical staffers confirmed at least two cases of COVID-19 on board.
  • A crew member aboard the MS Rotterdam sent Business Insider a memo breaking down a proposed rescue mission, in which healthy passengers from the Zaandam will transfer to the Rotterdam.
  • According to passengers on board the ship, the Zaandam has at least 144 sick passengers and crew members on board.
  • The Rotterdam was dispatched to supply the Zaandam with COVID-19 testing kits and other medical supplies.
  • The memo would indicate that the Rotterdam will also pick up all "well guests" from the Zaandam and sail north toward San Diego.
  • Holland America confirmed the deaths and number of those infected with COVID-19 in a statement.
  • Are you a cruise ship passenger or employee with a story to share? Email acain@businessinsider.com.
  • Visit Business Insider's homepage for more stories .

Four passengers have died onboard Holland America's stranded MS Zaandam cruise, according to a recording leaked to Business Insider from a sister ship sent to rescue healthy passengers from the stricken ship.

"I am also sad to share that four older Zaandam guests have passed away," the captain of the MS Rotterdam said in a recording of a shipwide announcement provided to Business Insider. "Three between yesterday and last night, and one a few days ago. Our thoughts and prayers are with their families and the Zaandam team is doing everything they can to support them during this difficult time."

A Holland America crew member sent Business Insider a recording of the Rotterdam's captain announcing the deaths, as well as news from medical staffers confirming at least two cases of COVID-19 on board the Zaandam. The Rotterdam rendezvoused with the Zaandam last night off the coast of Ecuador to deliver medical supplies, including COVID-19 tests. The Rotterdam currently has no guests on board, but crew members on the ship say it is staffed with a crew of 611.

And, according to a March 25 memo leaked by a Rotterdam crew member, the ship is now also tasked with rescuing healthy Zaandam guests. The crew member also sent Business Insider pictures of a printed memo dated March 25 and titled "Rotterdam Humanitarian Mission FAQ." The rescue response memo began with the question: "Why do we need to do this?"

"This is a humanitarian action to help a sister ship which has an outbreak of respiratory illness mainly affecting your team mates particularly food preparation and service staff," the Rotterdam memo said. "There is no other place for us to take the guests and no other means to provide assistance to the Zaandam and our fellow team members on board."

The document went on to say that ports and airports South America and Central America have been closed off to the Zaandam, and that "colleagues, fleet family members, and guests" on board "are in dire need." There were originally 1,243 guests and 586 crew members on the Zaandam. The ship's passengers have been confined to their state rooms on March 22 , with crew members relegated to delivering meals and collecting trash from each cabin.

The memo described a plan to sail the Rotterdam northwest, up to the United States, predicting that the ship could reach San Diego in about a week depending on its "fuel and provisions supply." From there, the Rotterdam would "disembark all guests and fly them home."

Only "well guests" would be elgible for the ship transfer, meaning anyone "showing no signs of illness, including fever." Sick guests and their "close contacts" would remain behind on the Zaandam. The document does not specify the plan for healthy Zaandam crew members.

The memo noted that members of the Zaandam "crew are showing influenza-like symptoms, such as fever and cough." Business Insider reported that 86 crew members and 58 guests had fallen ill, based on conversations with Zaandam passengers. The Rotterdam would resupply its sister ship with medical staff, supplies, and equipment, as well as "a number of COVID-19 test kits for use in identifying whether or not the illness is on board."

Passengers would be transferred onto the Rotterdam through a "secure corridor" that would "take them directly to their staterooms." As per that plan, no crew members from the Rotterdam would "come into close contact with anybody transferred and en route to their stateroom." All rescued guests would be required to "stay in isolation in their staterooms" for the duration of the journey, and meals will be provided through contactless delivery.

When it comes to personal protective equipment, the memo said that the Rotterdam crew would have enough surgical masks and gloves for the estimated seven to 10 day voyage up to the United States. It said that PPE would be "provided to wear based on their individual risk," singling out at-risk teams like medical, hotel, technical, and deck staffers.

'We are mariners'

Rotterdam crew members have told Business Insider that, despite the memo's attempts to quell their fears, they are frightened of becoming sick. They spoke of feeling that they were left without much of a choice by Holland America.

"Our crew do not agree and they did not give us any choice about it," one crew member said. "We will have to serve guests possible infected by COVID-19 without any equipment or instruction."

The crew member said they felt that Holland America "did not care for the health of our crew" by tasking the Rotterdam with the mission. The memo also repeatedly referenced crew members' concerns regarding safety.

"The chances that anyone will beome ill from well guests is very low," the memo said. "There is a higher chance of becoming ill traveling through an airport to get home than there is on the ship." It also noted that once at the port in the United States, these "well guests" will be "allowed to freely disembark go to a hotel or fly home with no restrictions."

"These guests are healthier than most people who travel, sail, and fly every day," the memo added. It said that crew members have a greater likelihood of being exposed to illness on their international flights home.

The document also provided Rotterdam crew members with a statement to give to family members. It described the transfer as "part of a humanitarian crisis mission in which the Rotterdam team is coming to the rescue of the Zaandam guests and crew."

Rotterdam crew members uncomfortable with the mission ought to "let us know how you feel and what your concerns honestly are," according to the memo.

"We should mention that nobody will be asked to do something that they don't want to do," the memo said. "But we would like you to think about your fellow team members on board Zaandam and the guests who are elderly and need your help, and what one would hope they would do for the Rotterdam team if you ended up in the same situation as that could have been easily been the case."

"Again, nobody will be pushed to do something that doesn't feel right to them," the document added.

The memo said that the situation onboard the Zaandam "escalated very rapidly," as an explanation for why crew members were not kept more aware of the nature of their mission aboard on the Rotterdam.

"We are mariners, and we consider this our duty and our obligation and so in the tradition we are proceeding with helping our sister ship the Zaandam," the captain of the Rotterdam said in the leaked audio. "Our guests and our fellow crew members on board need us. There are no easy choices here. In order to protect the Zaandam guests and crew members we need to move guests to the Rotterdam."

Are you a cruise ship passenger or employee with a story to share? Email acain@businessinsider.com.

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