Cruise lines are boosting measures on U.S. sailings to mitigate the spread of COVID-19 on ships as the delta variant continues to spread across the nation and globe.
Princess Cruises said Thursday that it would be adding a mask requirement on board its ships in addition to a testing requirement for passengers.
"As Princess Cruises continues with its successful restart of cruise operations the line is adapting to the evolving science around worldwide public health by advising booked guests of temporary changes in onboard mask and pre-cruise testing requirements for cruises in the United States," the cruise line said in a statement shared by spokesperson Negin Kamali.
All Princess ships that will sail in 2021 will have a passenger and crew vaccination requirement in accordance with the CDC. So, at least 95% of passengers and crew must show proof of vaccination to board.
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Starting on ships departing Sunday and later in U.S. waters, in "an abundance of caution" and in response to rising COVID-19 cases because of the delta variant, Princess said all passengers will be asked to wear masks in spaces such as elevators, shops, the casino and other select areas except when eating or drinking. Masks will be required during embarkation and disembarkation, too.
Additionally, starting on ships departing Aug. 15 and later, all passengers – including those vaccinated – must show a negative COVID-19 test (PCR or antigen) taken within three days of boarding.
Testing will not be available at the terminal.
Holland America Line, too, announced new requirements Thursday. Like Princess, Holland America has a vaccination requirement to sail.
"All guests will now be required to wear masks in certain indoor areas on board. This new policy goes into effect with all cruises that depart on or after Saturday, Aug. 7, through Oct. 31, 2021," the cruise line said in a release provided by spokesperson Erik Elvejord.
A testing requirement, too, will go into effect Aug. 14 through Oct. 31 for all passengers. A test must be taken within 72 hours of boarding. A "medically observed" negative PCR or antigen will be accepted. Testing will not be available in terminals in North America.
"For guests on Eurodam’s Greece cruises, an antigen test will be provided at the pier prior to boarding," Holland America said. "This test will be complimentary, and a negative result will satisfy our new testing requirements."
Carnival Cruise Line announced Wednesday it will require both vaccinated and unvaccinated passengers on its ships to wear masks in certain indoor spaces on board starting on cruises departing Saturday through Oct. 31.
It also added a testing requirement ahead of boarding. Carnival's new testing rule goes into effect on Aug. 14 and will go through Oct. 31. Passengers will be responsible for paying for testing and it will not be available at the terminal.
The Carnival Corp. subsidiaries' moves to heighten protocol comes after Royal Caribbean International announced that it is requiring passengers over the age of 2 to provide a negative coronavirus test before boarding ships with itineraries for five nights or longer in U.S. waters.
This policy was in place starting last Saturday and lasting through Aug. 31. The cruise line will accept both PCR and antigen negative results.
Before Saturday, vaccinated passengers were not required to show a negative test, spokesperson Lyan Sierra-Caro told USA TODAY on Friday. The added precaution comes as the delta variant continues to spread across the country.
The test must be administered no more than three days before boarding and passengers must show proof of their negative test result at check-in.
"All other testing requirements and policies are still in place. This is an additional layer of precaution to ensure the safety of everyone onboard," Royal Caribbean said in a statement provided by Sierra-Caro. "We will continue to monitor public health circumstances as they evolve and make necessary adjustments to our protocols."
This article originally appeared on USA TODAY: Princess, Carnival, Royal Caribbean adding new COVID-19 precautions