In this image from video, provided by the California National Guard, a helicopter carrying airmen with the 129th Rescue Wing flies over the Grand Princess cruise ship off the coast of California, March 5, 2020. (CALIFORNIA NATIONAL GUARD VIA AP)

Twenty-one people have tested positive for coronavirus aboard a cruise ship denied entry to San Francisco Bay this week after a number of passengers and crew developed flu-like symptoms on the vessel, which was linked to previously confirmed COVID-19 infections.

US Vice President Mike Pence, announcing results of the tests during a White House briefing, also said the cruise ship Grand Princess will be brought to an unspecified non-commercial port where all 2,400 some passengers and 1,100 crew members will be tested for coronavirus.

Those that need to be quarantined, will be quarantined. Those that require additional medical attention will receive it

Mike Pence, US Vice President

“Those that need to be quarantined, will be quarantined. Those that require additional medical attention will receive it,” Pence, recently appointed by US President Donald Trump as the government’s point man on the coronavirus outbreak, told reporters.

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“But with regard to the 1,100-member crew, we anticipate that they will be quarantined on the ship, will not need to disembark,” he said. 

Pence added: “It’s very likely that the crew on the Grand Princess was exposed on two different outings, and we know the coronavirus manifested among the previous passengers.”

Appearing separately on a visit to the headquarters of the US Centers for Disease Control and Prevention in Atlanta, before the initial cruise ship test results were released, Trump said he would prefer the Grand Princess passengers remain on the ship for the duration of a quarantine.

Otherwise, he said, allowing passengers back onto US soil who might become sick later would end up increasing the number of coronavirus cases in the country.

“I don’t need to have the numbers double because of one ship that wasn’t our fault,” he said.

PASSENGERS UNCERTAIN OF FATE

Diagnostic test kits were flown by an Air National Guard helicopter on Thursday to the cruise ship, where medical staff took samples from 46 passengers and crew to determine if they have contracted the respiratory virus.

The samples were carried back to a state laboratory in the Bay area. Pence said 21 of the tests came back positive, 24 were negative and one was inconclusive.

One of the passengers aboard the ship, Debbie Loftus, said they had not been informed of the results of the testing before Pence announced it, and were uncertain about when they can return to their homes.

State and local officials acted to halt the cruise liner after learning people aboard had fallen ill and two passengers who traveled on the same vessel last month to Mexico later tested positive for coronavirus.

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One, an elderly man from Placer County near Sacramento with underlying health conditions, died this week, marking the first documented coronavirus fatality in California. The other, from the Bay area, was described by Newsom as gravely sick.

Health officials are also seeking to contact some 2,500 passengers who disembarked in San Francisco on Feb 21 after the earlier cruise to Mexico

Health officials say both individuals likely contracted the virus aboard the ship.

A third passenger from the Mexico trip, a Canadian woman from the province of Alberta, has since been reported by health officials there to have tested positive.

ELDERLY AT RISK

Minnesota health officials said on Friday the state’s first coronavirus diagnosis was an older Ramsey County resident “who recently traveled on a cruise ship with a known COVID-19 case.” But a spokesman for the Minnesota Health Department said he was not certain whether the cruise ship in question was the Grand Princess or some other vessel.

Pence urged elderly people with serious underlying medical conditions “To think carefully about travel.”

Health officials are also seeking to contact some 2,500 passengers who disembarked in San Francisco on Feb 21 after the earlier cruise to Mexico.

The Grand Princess situation was reminiscent of the Diamond Princess cruise liner that was quarantined off Japan in February and was for a time the largest concentration of coronavirus cases outside China.

Experts have criticized Japanese bureaucrats’ handling of the onboard quarantine, as ultimately about 700 people were infected and six have died.

Both ships are owned by Princess Cruises, a unit of Carnival Corp, the world’s largest cruise operator.