A cruise ship passenger died from coronavirus less than two weeks after he returned home to California.
The death was linked to Princess Cruises’ ship Grand Princess, which is being held off the California coast to enable federal health officials to screen people on board.
Some were on an earlier cruise with the California victim.
Officials are trying to locate hundreds of other passengers who left the ship in San Francisco last month after a cruise to Mexico.
A Princess Cruises spokesperson said: “After collaboration with and guidance from the US Centers of Disease Control (CDC) and local authorities, Princess Cruises can confirm the following proactive measures to ensure the continued safety and well-being of our guests on board Grand Princess.
“While there are no confirmed cases of Covid-19 currently onboard, the CDC has identified groups of guests and crew who will be tested before arrival into San Francisco.
“There are fewer than 100 guests and crew identified for testing, including all in-transit guests – guests who sailed the previous Mexico voyage and remained onboard for the current Hawaii voyage – those guests and crew who have experienced influenza-like illness symptoms on this voyage, and guests currently under care for respiratory illness.
“To facilitate this testing, the US Coast Guard will deliver sampling kits to the ship the morning of March 5 via helicopter.
“Our onboard medical team will administer the test and the samples will be sent in batches by helicopter to a lab in Richmond, California across the bay from San Francisco.”
The line added: “Public health officials have advised that no guests will be permitted to disembark until all results have been received.
“All guests who have been identified for testing have been asked to remain in their staterooms. We will continue to proceed under the guidance of the US CDC and local authorities.”
The line has cancelled an upcoming Grand Princess Hawaii cruise departing on March 7.
All passengers will receive a full refund and a future cruise credit equal to 100% of the cruise fare paid on this voyage.