In an aerial view, the Royal Caribbean Freedom of the Seas (L) prepares to set sail from Port Miami during the first U.S. test cruise to test COVID-19 protocols on June 20, 2021 in Miami, Florida.

Joe Raedle | Getty Images

Royal Caribbean Cruises’ shares fell more than 4% on Friday after six passengers aboard their Adventure of the Seas ship tested positive for Covid-19.

The four of these guests were fully vaccinated and did not travel together. The cases were discovered during routine testing.

Three of the four fully vaccinated passengers had no symptoms and the fourth passenger had mild symptoms, Royal Caribbean said in a statement. The two unvaccinated guests are minors, travel in the same group and are asymptomatic.

The six guests were immediately quarantined and their close contacts identified and tested. They all tested negative, Royal Caribbean said.

“Each guest and their immediate tour groups disembark in Freeport, The Bahamas today and travel home separately on private transportation,” said the cruise operator.

When the cruise left Nassau, Bahamas on Saturday, the guests had to prove a negative PCR test. Unvaccinated minors were required to take another test upon check-in. All had tested negative before boarding, said a company spokesman.

Due to the rapidly spreading delta coronavirus variant, the shipping company will expand its test procedures for cruises from the United States of five nights or more. Passengers must undergo a negative test before boarding, CEO Michael Bayley said in a Facebook post. He added that the tests can be taken within 3 days of embarkation. The new policy applies from July 31 to August 31.

“Even if the vast majority of our on-board population is heavily vaccinated, we are seeing more Covid-positive cases with vaccinated guests,” Bayley said in the Post. “The Delta variant is now spreading rapidly with over 92,000 new infections in the US alone yesterday and in Florida, one of the most important markets in the industry, there were over 17,000 cases yesterday.”

“We are aware that this will not make many guests happy, but rather that it will comfort many guests. We are trying our best to provide a safe, healthy, and fun vacation to all of our guests, crew, and the communities we visit during these challenging times, ”said Bayley.