Sharon Stone is a fan of cruises. She cruises with her husband and they cruised with their children when they were younger. She even cruised with Disney through a particularly nasty outbreak of norovirus several years ago. In total, the Florida resident has been on nearly 15 cruises and is planning another vacation through Royal Caribbean in May. But, as reports circulate of travelers infected with coronavirus (COVID-19) aboard ships, amid stories of quarantines and mass infection across the globe, Stone is now having second thoughts.

“I’m feeling very nervous,” says Stone, who is in her 60s.

A new program from Royal Caribbean will give Stone and her husband the option to postpone her vacation without incurring fees, but she’s yet to make a decision on what to do. Convincing Stone, and the tens of millions of potential travelers like her, that taking a cruise vacation is perfectly safe, is the task weighing on the industry as the coronavirus continues to spread.

“It’s going to take a miracle for the cruise-line industry to recover in less than a decade,” says Gene Grabowski, a partner at crisis communications firm kglobal.

In recent years, business has been booming for the category. Last year, some 30 million consumers took cruises, up from 28.2 million in 2018, according to the Cruise International Association, a trade group. Norwegian Cruise Lines recently unveiled a massive integration deal with singer Kelly Clarkson.

Yet, such robust figures are now under threat. Over the weekend, the State Department warned consumers against traveling via ship, due to “increased risk” of catching the virus. Experts expect that marketers will need to change their advertising tactics and plan for rougher seas ahead.

“All sectors of travel are dealing with a significant drop in demand, and we haven’t seen a widespread drop in global demand for travel in years,” says Amy Hinote, founder and editor-in-chief of VRM Intel, a travel publication.

Grabowski says that, already, there was some expected softening of the industry, which has had no trouble attracting older travelers but has been challenged with booking Gen Z and millennials, who crave more sustainable trips and often maker cruises the butt of jokes around food-borne illnesses.

“Already, there was a lot of negative publicity but this is the icing on the cake,” says Grabowski. “The ships are basically seen right now as floating petri dishes and that is going to frighten a lot of potential customers away.”

The cruise industry is also dependent on discretionary spending, unlike airlines which are often boosted by business travel, experts say.

In the next few weeks, Grabowski says individual cruise lines, including Norwegian, Royal Caribbean and Carnival, need to prove to customers that they are taking all precautions. He advises airing videos that clearly demonstrate how each ship is sanitized and cleaned.

Cruise line operators should also be teaming up with health-care experts to verify the safety of the ships, and they should publicize such partnerships. Experts say such messaging should be made via social channels and that it may be premature to do much paid marketing at this stage.

Earlier this month, several cruise operators, including Royal Caribbean and Norwegian, introduced new policies to their customers that allow for credits if a traveler chooses to delay a trip. Norwegian’s “Peace of Mind” offer lets customers cancel up to 48 hours ahead of a trip and receive a full credit for use on a new cruise through Dec. 31, 2022. The marketer declined to comment further.

Stone is considering using Royal Caribbean’s “Cruise with Confidence” policy, which she calls a smart move. She says cruises typically cost around $1,000 for a couple for a three-night trip, but can run upwards of $3,500 a person for two-week trans-Atlantic jaunts.

After the virus begins to weaken and news reports of new cases decrease, cruise marketers should begin ramping up their advertising. Grabowski advises featuring well-known, popular celebrities in campaigns and inviting members of the press onboard ships for press junkets.

“Marketing strategies have to change,” says Hinote, who notes that in the recent boom years, travel marketers were purely price-driven in their advertising. But she says brands will need to step it up a notch now to inspire travel and boost demand.

“We see this as a time for an advertising revolution of all sectors of travel, one that will be more creative and professional and one that inspires people to travel, educates the market about new leisure travel opportunities and demonstrates the many benefits of taking a vacation,” she says. “It’s finally time to get some creative genius injected into an industry whose marketing has been stale and boring for a long time.”

Correction: Norwegian Cruise Lines is allowing customers to use credits on trips through Dec. 31, 2022—this fact was misstated in an earlier version of this article