Carnival Cruise Line has brought in stricter mask mandates and testing requirements across the fleet following the discovery of COVID-19 infections aboard Carnival Vista.

Carnival Cruise Line said in a statement that “a small number” of passengers aboard Carnival Vista had tested positive for coronavirus, and has tightened its health and safety protocols fleetwide.

Carnival Breeze and the Carnival Vista return to the Port of Galveston ahead of their cruise restart.

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The new measures were due to be introduced later this week, but were made effective immediately Wednesday after several passengers aboard Carnival Vista tested positive for COVID-19.

“Our pre-established protocols of vaccinated guests and crew, testing, enhanced medical capabilities and contact tracing anticipated the potential for positive cases, and they are designed to adapt to various scenarios,” Carnival said in a statement.

“We have identified and tested close contacts and anyone who tested positive is in isolation,” it added.

The new measures, which were first introduced by Brand Ambassador and Senior Cruise Director of Carnival Cruise Line, John Heald earlier this week, involve mandatory mask wearing by all guests at all times indoors.

This applies to vaccinated and unvaccinated guests alike, while all guests will also now need to be tested for COVID-19 at least three days prior to boarding the ship.

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“In any (indoor) area where many people are gathered and when you’re not eating or drinking, we are going to require you to wear a face mask, and this is for all guests, not just those who are unvaccinated,” said Heald in a Facebook video.

“[Testing will also be mandatory] for all guests, (including) fully vaccinated,” Heald added. “You are going to need a negative antigen test taken within three days of your cruise, and you’ll need to show proof of this.”

Heald had explained that the cruise line was introducing these rules in order to “keep cruising going”, but now a statement from Carnival Cruise Line has made the rules effective immediately rather than by August 7th as initially planned (the testing requirements will still come into effect from August 14th).

The positive cases aboard Carnival Vista, which is sailing in the Caribbean out of Galveston, Texas, take the total number of passengers infected with COVID-19 while on a cruise since July last year past 221.

However, as Carnival Cruise Line has not elaborated on the total number of guests infected, it’s impossible to know the full number.

Carnival Vista is continuing with her cruise as planned, and the guests who tested positive for COVID-19 are being kept in isolation aboard the vessel, according to Carnival.

The cruise line said it will continue to operate vaccinated cruises as defined by the US Centers for Disease Control and Prevention. The CDC requires 95% of both passengers and crew to be vaccinated. Carnival said its crew is fully vaccinated.