As the Omicron variant of the coronavirus continues to surge onboard cruise ships, forcing several cruise lines to cancel and postpone voyages, Atlantis Events, a gay and lesbian tour operator, is preparing to launch one of its biggest events on Sunday: a 5,500-person Caribbean cruise marking the company’s 30th anniversary.

Even as the pandemic is raging around the world and the Centers for Disease Control and Prevention has issued a stark warning telling Americans to avoid travel on cruise ships, regardless of their vaccination status, Atlantis insists that its vaccination mandate, testing requirements and health protocols are enough to provide a safe environment for guests throughout the voyage. Many passengers are convinced.

“It’s time to start living our lives again and vaccines and tests allow us to do that. This isn’t Covid 2020,” said Andre Mayer, a graphic designer from Germany who paid more than $4,000 for the weeklong cruise on board Royal Caribbean’s Oasis of the Seas. “This is going to be the wildest party for our community in two years. I’m talking dirty dancing, sex, drugs, raves, orgies and sweet, sweet freedom.”

For the hundreds of cruise passengers who contracted the coronavirus on board other ships in recent weeks, many falling ill and spending days in quarantine, their experience couldn’t have been further from the carefree vacation that Mr. Mayer anticipates. After testing positive, many hoped to isolate in their airy rooms with balconies, but were transferred to basic quarantine facilities — some of them without windows — and served food that they described as cold and hideous.

For some booked on the Atlantis anniversary cruise, these reports and the Omicron wave of the virus is causing them to reconsider their plans. But the company’s strict cancellation policy does not offer refunds for changes made within 60 days of departure, forcing guests to weigh health risks against losing thousands of dollars.

“The Covid reality changes so quickly that there needs to be more flexibility,” said Aiden Morgan, a 44-year-old dance teacher from Boston. Mr. Morgan sold his ticket on Facebook, but was only offered a $1,480 for his $3,800 ticket.

“I’m getting a lot of pressure from my friends to go and believe me, I really want to go and get it on, but it just seems crazy to me to risk getting sick and being trapped on a boat,” Mr. Morgan said. “Some nights I lose sleep and get the sweats just thinking about being in a cold room all alone with Covid.”

Rich Campbell, chief executive officer of Atlantis Events, said that his events company was not able to offer the same flexibility as billion-dollar cruise lines, which have many fleets and sailings to transfer bookings, and the financial resources to offer refunds.

“In order to exist we take massive risks to operate these charters,” Mr. Campbell said. “We signed a contract with the cruise line that cannot be changed or canceled. If I told Royal Caribbean that I was canceling the cruise tomorrow, they would come back and say ‘great but you still owe us the money.’ ”

Out of the 2,700 rooms sold, Mr. Campbell said only 35 have been canceled since Jan. 1.

For guests who cannot travel because of government restrictions or lockdowns, Atlantis is showing more flexibility and issuing credits for future cruises, Mr. Campbell said. Because of the fast-changing circumstances of the pandemic, he said, the company is approaching cancellation requests on a case-by-case basis and trying to accommodate as many people as possible.

“We are here to take care of people and we are doing our best,” he said. “But if someone comes to us and just says they want their money back, because they don’t feel comfortable going on the cruise, then we recommend that they take out ‘cancel for any reason’ travel insurance.”

Since restarting operations in the United States in June, many cruise lines and tour operators have adopted flexible cancellation policies, offering credit or refunds to customers who want to make itinerary changes because of the coronavirus.

Before the pandemic, Atlantic Events hosted more than 25,000 guests each year, organizing specialty gay and lesbian events on cruise ships and resorts around the world. Last year it was forced to cancel or postpone several events, including its 30th anniversary cruise.

“We had almost two years with no income, and we are a tiny self-financed company. It was a huge challenge to survive,” Mr. Campbell said.

While the company does not offer refunds, it says that the health and safety of its guests is a top priority and it will be enforcing Royal Caribbean’s health and safety protocols, which includes a mask mandate indoors except while eating and drinking and in crowded spaces outdoors. Royal Caribbean officials say that while the Omicron variant has driven up cases on board its ships in recent weeks, most infections have been mild and have not resulted in severe illness. Still, with a growing number of crew members and passengers contracting the virus, the cruise line, like other cruise companies, has canceled several voyages this month in what it said was “an abundance of caution” as a result of “ongoing Covid-related circumstances.”

Passengers booked on the Atlantis cruise are closely watching the Celebrity Millennium cruise ship, which was chartered by another L.G.B.T travel company this week for a seven-night Caribbean cruise. The capacity for that ship is much smaller, at 2,218 passengers, but coronavirus cases have been reported to the C.D.C. and reached their threshold for an investigation.

Andrew Dubry is a model and entrepreneur from Arizona who has been on several Atlantis cruises. Though a fan of their events, he called on the company, using Facebook, to cancel the cruise and reschedule for a later date. “So many people feel forced to go because they can’t get their money back, it’s not right,” Mr. Dubry said. “Maybe they are worried that it will be empty if they give people the option to cancel, but it’s their 30th anniversary. I don’t see why they don’t just reschedule and make it the big fun party at a better time.”

Ron Davis, a 50-year-old talent manager from Nashville who will be embarking on his 26th Atlantis cruise on Sunday, said the calls to cancel the cruise are overblown and exacerbated by the stigma against gay cruises that presumes they are all drug-fueled sex parties with no limits.

“The cruise is whatever you make of it and there is something for everyone,” Mr. Davis said. “I have never been part of an orgy, I have never done cocaine off a stair rail. Sure, if you want that you can find it, but it’s not all people having rampant sex out in the open.”

For Mr. Davis, the upcoming cruise does not feel any more dangerous than taking a flight, or going for happy hour at his local bar where customers are not tested beforehand.

“I don’t think I’m bulletproof, but I’m doubled vaxxed and boosted and I’m careful,” he said.

Mr. Campbell, the Atlantis chief executive, says that while the 30th anniversary cruise will be a big event for the company, it will be more restricted compared to previous years.

“There will be safety protocols and walls and barriers and things in place designed to do the opposite of the business we’re in, which is to bring people together,” he said.

Still, for many guests, this will be their first big outing since pandemic restrictions were imposed in 2020. Some passengers expect that people who have been cooped up at home will try to make up for lost time.

“So many people have been starved of company and human touch,” said Costas Raptis, 41, a banker from Greece who sold his ticket online because of fears that he will have to quarantine if he catches the virus. “Everyone will party hard and hook up and trust me: If they get a few little Covid symptoms, they are not going to tell nobody.”

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