Carnival cruise ship returns to Miami with ‘small number’ of coronavirus cases.

A Carnival Cruise Line ship returned to Miami on Sunday after multiple people onboard tested positive for the coronavirus, the cruise line said.

The ship, the Carnival Freedom, departed from Miami on Dec. 18 on an eight-day cruise when “a small number on board” were isolated because of a positive coronavirus test, the cruise line said in a statement. The company did not say how many guests or crew members were infected.

“Our protocols anticipate this possibility and we implement and adapt them as necessary to protect the health and safety of our guests and crew,’’ the cruise line said. “This was a vaccinated cruise and all guests were also tested” before the ship departed, the company said.

The cruise line said that “the rapid spread of the Omicron variant may shape how some destination authorities with limited medical resources may view even a small number of cases.”

The ship, which can carry nearly 3,000 passengers and 1,150 crew members, was not able to make planned stops in Bonaire and Aruba and instead made an “alternative visit” to Amber Cove in the Dominican Republic, a company spokesman said.

One passenger shared on Twitter a photo of a letter from the captain who apologized for the stops and said that passengers would receive credit to use toward a future cruise.

The Carnival Freedom is the latest Florida-based cruise to be disrupted as the highly contagious Omicron variant drives up cases in much of the United States and Europe. Many lines have adjusted their rules for masking, testing and vaccines in response to the surge.

Last week, 55 fully vaccinated passengers and crew members on the Royal Caribbean ship Odyssey of the Seas tested positive, the cruise line said. The ship returned to its home port in Fort Lauderdale, Fla., on Sunday. It was the second Royal Caribbean ship from Florida to report positive cases this month, after 48 people aboard the Symphony of the Seas tested positive for Covid-19 during a seven-night Caribbean cruise that departed from Miami.

The company said that all of its crew members were fully vaccinated against Covid-19 and were tested weekly.