Doug Brode is an avid cruiser, with about 50 sailings behind him and hopes for a European river cruise ahead.

But the 76-year-old Ontario resident won’t even think about getting on a ship again until he’s gotten the coronavirus vaccine — and he hopes cruise lines are thinking the same way.

“I think the cruise lines should make it a requirement and have proof,” said Brode, a retired technical writer.

Cruise fans like Brode are watching to see what the industry will do now that vaccines are being distributed to some populations — albeit more slowly than expected — and some countries are allowing travelers to skip quarantine if they’re vaccinated. While the majority of the cruise industry is still not sailing with passengers, a few lines have started limited cruising outside the United States.

One small cruise line in the United Kingdom has announced it will sail with only vaccinated passengers. Saga Cruises, a two-ship operator for passengers 50 and older, said last week that it was delaying the restart of cruises to give passengers time to get fully vaccinated. That means they would have to get both doses and wait at least 14 days before departing.

“We have made the decision not to allow a guest to travel with us if they choose not to receive the vaccine,” the company said in a question-and-answer section of its website. “The majority of our guests fall into the at-risk age bracket and our priority is their safety and wellbeing.”

So far, Saga appears to be standing alone among cruise lines in its requirement.

The CEO of one other cruise company, Norwegian Cruise Line Holdings, said last month during a Zoom “fireside chat” that the company’s lawyers were examining whether passengers could be required to get the vaccine. He said crew would have to be vaccinated.

“It’s too early to tell whether we have the legal standing to mandate that you take a vaccine or else you can’t come on board,” Norwegian CEO Frank Del Rio said during the conversation with John Lovell, president of Travel Leaders Group. He said he would need to balance the legal advice he gets with any vaccination demands from destinations.

“So if the lawyers tell me, ‘You can’t do it, Frank,' and the port of XYZ says ‘You can’t come,’ well, I guess we’re not coming to that port,” he said.

In a statement, the company said last week that it was closely monitoring vaccine developments.

“We are exploring all options regarding vaccinations for guests and crew and it is our intention that all crew members be vaccinated before boarding our vessels to begin their duties, subject to availability of the vaccine,” the statement said. “We will continue to partner with global and domestic authorities and the Healthy Sail Panel, our team of leading expert advisors, to explore all options necessary to protect guests, crew and the communities visited.”

The world’s two largest operators, Carnival Corp. and Royal Caribbean Group, have taken a wait-and-see approach as they work with the Centers for Disease Control and Prevention on requirements to start sailing again from the United States.

“We are still in the process of finalizing the details for our return to service and as soon as we have more information on our requirements, we will let our guests know,” Royal Caribbean Group said in a statement.

During an earnings call earlier this month, Carnival Corp. CEO Arnold Donald pointed out that vaccine distribution is still an issue: “We’ll let it evolve over time, and we’ll make the most prudent decision when the time comes,” he said.

Carnival Corp. spokesman Roger Frizzell called vaccines an “important breakthrough” for the industry last week.

“We are reviewing the various vaccines, but we have not made any decisions on next steps at this point,” he said.

The industry’s trade group, Cruise Lines International Association, said that the vaccines are “truly game changers,” but not the only way to respond to the pandemic.

“It’s important to note that the roll-out of vaccines across the world will take some considerable time and many uncertainties remain,” spokeswoman Bari Golin-Blaugrund said in an email. “Having engaged with leading experts in health and science for many months to identify and implement effective measures to mitigate risk in a cruise setting, the cruise industry recognizes that no single measure is alone effective and that a multi-layered approach is the right one.”

A CDC spokeswoman said vaccines can be used to reduce the risk of travel-related transmission of the virus, though also pointed out that it should not be treated as a stand-alone solution.

“Vaccination, along with other preventive measures, including testing before and after travel, wearing a mask, social distancing, frequent handwashing, and cleaning and disinfecting frequently touched surfaces, will be another effective strategy available for reducing COVID-19 transmission associated with travel, including cruising,” spokeswoman Caitlin Shockey said in an email.

The World Health Organization has cautioned against requiring the vaccine for travel, citing limited availability and questions that still remain about how effective it is in reducing transmission. The World Travel and Tourism Council warned that vaccine requirements would amount to discrimination.

While some frequent cruisers have vowed not to set foot on a ship if it means they would have to get vaccinated, many seem open to the idea.

The cruise news and review site Cruise Critic surveyed its readers recently asking if they would still cruise if they were required to get the vaccine. Of the nearly 2,800 who responded, 81 percent said they would sail if vaccines were mandatory; 5 percent said they would not, and 14 percent said they were not sure.

“Our readers are cruisers, and that’s their preferred vacation of choice,” said Colleen McDaniel, Cruise Critic’s editor in chief. “They are willing to do whatever it takes to get back on board cruise ships.”

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