(Reuters)

At least 17 COVID-19 cases, including a probable case of the Omicron variant, have been detected among passengers and crew on a cruise ship that disembarked in New Orleans over the weekend, Louisiana health officials said.

The Norwegian Breakaway, operated by Norwegian Cruise Line Holdings Ltd and carrying more than 3,200 individuals, departed New Orleans on November 28 and made stops in Belize, Honduras and Mexico before returning to the Louisiana port on Sunday (December 5), officials said.

The probable Omicron case was identified in a crew member who is not a Louisiana resident and has not left the ship, health officials said.

Officials said all passengers were being tested for COVID-19 before leaving the ship, and those who tested positive would either travel to their residence in a personal vehicle or self-isolate in accommodations provided by Norwegian Cruise Line.

The United States has seen a rise in COVID-19 cases in recent weeks, and the emergence of the new Omicron variant has sparked concern as health officials rush to discern its severity. At least a third of states have reported Omicron cases, though the Delta variant remains the country’s dominant strain the coronavirus.

After outbreaks on ships prompted US health officials to suspend cruising early in the pandemic, leading to billion-dollar losses, pent-up demand for leisure travel and the roll-out of COVID-19 vaccines have helped the industry rebound since sailing resumed this summer. Last month, Norwegian Cruise Line forecast a return to profitability in the second half of 2022.

All major cruise operators departing from US ports, including Norwegian Cruise Lines, require guests and crew to be fully vaccinated. Passengers are required to have received the final dose of an authorised COVID-19 vaccine at least 14 days before the beginning of the cruise.

Norwegian also requires all guests to take a COVID-19 antigen test prior to boarding. The company said all of the positive cases on the cruise ship that docked on Sunday were asymptomatic.

Some passengers told WVUE-TV they had been informed of the positive cases, while others said they were unaware.

“It would have been nice to have known. We would have taken maybe a few more precautions,” Don Canole, a passenger from North Carolina, told the television station.

Passengers agree to accept the risks including death from travelling during the pandemic, according to Norwegian’s ticket, which recommends passengers seek the advice of a doctor before boarding. The contract also specifically says passengers accept the risks of new COVID variants and bear the costs of quarantine or other restrictions imposed by authorities due to the virus.

Increased cruise travel has led to COVID-19 cases among passengers and crew members despite high vaccination rates in both groups, the CDC has said. From June 26 to October 21, there were 1,359 confirmed coronavirus cases reported to the CDC by cruise ships, including several large outbreaks.

Despite the strict safety protocols implemented by cruise ships, ensuring passengers end their trips are infection-free has proven difficult.

There have been instances of passengers who denied being symptomatic or waited several days to report symptoms, the health agency said. One fully vaccinated passenger who was symptomatic for COVID-19 but denied having symptoms died three days after boarding for reasons related to the virus, according to the CDC.