The Royal Caribbean cruise ship will be seen on the Hudson River in New York City, United States, on August 18, 2021 as the region’s first cruise ship docks back in New York Harbor.

Tayfun Coskun | Anadolu Agency | Getty Images

The Centers for Disease Control and Prevention said Friday that travelers at high risk of serious complications from Covid-19 should avoid cruises regardless of their vaccination status.

The updated guidelines also recommended that travelers who are not fully vaccinated should not cruise.

The new council follows several coronavirus outbreaks reported on board cruise lines, according to the CDC.

While the agency doesn’t introduce the same masking requirements that apply to planes, trains, and other public transportation, it suggested that face-covering be worn for cruise passengers in common areas.

“The virus that causes Covid-19 spreads easily between people in close proximity on board ships, and the likelihood of getting Covid-19 on cruise lines is high,” the CDC said in its updated guidance.

The agency advised all travelers, regardless of their vaccination status, to get tested one to three days before a cruise and three to five days after their return. Anyone taking a cruise should be in quarantine for seven days after returning, even if they tested negative for the virus.

The new policy comes just a week after the Belize Tourism Board announced that 27 people on board a Carnival cruise tested positive for Covid.

During Friday’s extended trading, Carnival Cruises shares fell more than 2%, Norwegian Cruise Line shares fell nearly 3%, and Royal Caribbean Cruises shares fell more than 2%.

After the industry closed at the beginning of the pandemic due to multiple outbreaks on board ships, the CDC has enforced strict guidelines to prevent similar events from occurring.

Of the three cruise lines, Royal Caribbean Cruises was the first to return to operations and had few cases on board ships, which was the target, according to CEO and Chairman Richard Fain.

Royal Caribbean Cruises and Carnival Cruises have allowed some unvaccinated passengers on board ships, but Norwegian Cruise Line has not.

Norwegian even filed a lawsuit against the Florida Surgeon General to halt a state ban that prevented companies from requiring customers to provide proof of Covid vaccination. The cruise company was granted a temporary stay in enforcement, but Florida has filed an appeal.