Cruise giant Carnival grapples with a significant COVID-19 outbreak on ship

At least 27 people on a Carnival Cruise Line ship sailing in the Caribbean have tested positive for COVID-19 -- the biggest recorded outbreak of the illness on a cruise vessel in the region since Caribbean cruising resumed in June.

The Galveston, Texas-based Carnival Vista arrived in Belize on Wednesday with 26 crew members and one passenger on board who had tested positive for COVID-19, according to a statement from the Belize Tourism Board.

All the crew and the passenger who tested positive were vaccinated, the tourism board said, and are experiencing either mild symptoms or no symptoms at all.

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The statement from the Belize Tourism Board put a concrete number on a COVID-19 outbreak that has been simmering for several days and that Carnival appears to have tried to downplay. Carnival in recent days only has said that it is "managing a small number of positive [COVID-19] cases" on board Carnival Vista -- a phrase the line used again Friday in a statement sent to TPG.

In theory, there could be additional cases on board Carnival Vista that have gone undetected, as Carnival has not been regularly testing most passengers on the ship. The line only is regularly testing crew on the ship on a rotating basis every few days.

Still, the Belize Tourism Board said Carnival did contact tracing for all 27 crew and passengers who tested positive, testing all "close contacts" of the 27 people, and found no additional COVID-19 cases. More than 900 people on the ship were tested for COVID-19 as part of this contact tracing process, the tourism board said.

Carnival Vista is sailing with more than 4,000 people on board -- 1,441 crew members and 2,895 passengers.

All the crew and passengers who have tested positive have been quarantined on the ship, in keeping with the latest COVID-19 guidelines for cruise ships issued by the U.S. Centers for Disease Control and Prevention (CDC).

While other cruise ships that have restarted operations in the Caribbean since June have experienced isolated cases of crew and passengers testing positive for COVID-19, the numbers reported have generally been very low. Celebrity Cruises reported two cases of passengers testing positive for COVID-19 on a Caribbean sailing in June, for example, and Royal Caribbean recently reported six cases on a sailing.

In its statement, the Belize Tourism Board noted that it met virtually with officials on the Carnival Vista in advance of its arrival in Belize on Wednesday to discuss the positive COVID-19 cases on board and was assured that "the infected crew and passenger do not pose a threat to guests, crew or frontline workers in Belize."

Carnival restarted departures out of U.S. ports on July 3 after a 16-month-long halt to operations caused by the coronavirus pandemic.

Like many cruise lines that have restarted departures in recent months, Carnival is requiring that all passengers be vaccinated for COVID-19, though it is making exceptions for a small number of children who are not old enough to be vaccinated and passengers with medical issues.

Related: The ultimate guide to Carnival ships

On the current sailing, nearly 97% of passengers are vaccinated.

The line also has implemented new mask-wearing rules for some indoor areas of its ships and is adding a requirement, effective Saturday, that passengers show proof of a negative COVID-19 test to board a vessel. The COVID-19 test must be taken within three days of boarding a ship.

Carnival Vista is operating a seven-night cruise to the Western Caribbean out of Galveston that began on Saturday and has included calls in Honduras, Belize and Cozumel, Mexico. All of the stops went on as planned despite the COVID-19 cases on board. The ship currently is on its way back to Galveston, as scheduled, and will be back in the Texas port Saturday morning.

In its statement to TPG, Carnival said the next departure of the ship, later on Saturday, would take place.

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