One might think the recent outbreaks of hantavirus aboard the Hondius and norovirus on the Ambition would rattle Colleen McDaniel’s enthusiasm for the mode of travel. Not so.
“I’m currently on a European river cruise, and no one is talking about illness,” the Colorado-based editor in chief of review site Cruise Critic wrote in an email. “People are enjoying their excursions along the Rhine River, chatting socially and having a great time.”
Infectious-disease experts say that while viruses can transmit anywhere large groups gather, the environment on cruise ships can amplify transmission. But with a 15-month hiatusduring the coronavirus pandemic a distant memory, cruise ships are busting records, with U.S. travelers leading the charge. And industry watchers don’t see the latest virus outbreaks changing anything.
The United States was the largest source of cruise ship passengers in the world last year, with 20.5 million people embarking on a trip, according to the latest figures from the Cruise Lines International Association, released in April. That’s a 7.5 percent increase from 2024, and up from the nearly 12 million passengers recorded in 2022, the agency said.
The number is expected to grow in 2026, according to AAA.
How viruses spread
A cruise ship “creates a perfect opportunity” for disease to spread quickly, said Vikram Niranjan, assistant professor in public health at Ireland’s University of Limerick School of Medicine. “Unlike a flight, we are not transferring people from place A to place B. We are housing them together for seven to 14 days,” he said, highlighting the shared dining facilities, theaters, gyms and spas.
Complex water and ventilation systems, semi-enclosed environments like cabins and elevators, as well as guests who skew older and may have underlying health conditions or weakened immune systems, can also help a virus spread, Niranjan added.
While deadly or little-known viruses grab headlines — like the Andes strain of hantavirus found recently on the Hondius polar expedition ship and the then-unfamiliar coronavirus that made the Diamond Princess famous in 2020 — the most common disease on cruises “by far” is norovirus, a highly infectious gastrointestinal illness, said Nicole Iovine, a professor of medicine at UF Health Shands Hospital in Florida.
Centralized food preparation can help spread infection, Iovine said. “The infectious dose for norovirus is very low, meaning that it only takes a few viral particles to cause an infection, further increasing the risk of infection.”
The ‘cruise ship virus’
Norovirus features heavily in a Centers for Disease Control and Prevention tally of disease on cruise ships that have docked at U.S. ports.There have been four outbreaks of gastrointestinal illness this year, the agency said, defining an outbreak as when more than 3 percent of passengers or crew report symptoms. In 2025, at least 23 ships reported outbreaks, primarily of norovirus, the CDC stated, while nearly 20 cases were reported a year earlier.
Despite norovirus being dubbed the “cruise ship virus,” cruise ships account for only 1 percent of the 2,500 norovirus outbreaks in the U.S. each year, according to the CDC. The most common settings for them to occur are health care facilities and schools, the agency said.
But, the virus can be “especially challenging to control” on cruise ships because of close quarters, shared dining, as well as people and food coming on and off the ship, the CDC said. “Repeated outbreaks on consecutive cruises may also result from infected crew or environmental contamination. This is because norovirus can persist on surfaces for days or weeks and is resistant to many common disinfectants.”
Still, McDaniel said the situation on the Ambition off the coast of France — which was forced to modify its journey and hold passengers on board while the illness was being investigated — was “incredibly uncommon.” If illness is detected on board, ships typically step up cleaning, isolate sick people and collect samples for testing, according to the CDC. The agency might also ask cruise operators to notify port authorities and delay bringing passengers on board for the next voyage.
Demand remains strong
Industry experts say outbreaks haven’t put a damper on interest in cruise travel. “Conversations on our forums currently show that, while there’s interest in the situation and concern for the affected travelers, it’s not something that’s a huge concern, personally, for those cruisers,” McDaniel said.
On social media, commenters on the Facebook page of Ambassador Cruise Line, the owner of the Ambition, appeared sanguine about the norovirus outbreak. “Top marks for Ambassador keeping everyone informed and also for the crew of the Ambition for rising to the situation,” wroteone user.
“I’m sure this sort of thing happens all of the time,” said another, who added: “Just a shame, publicity wise, that it happened at the same time as the outbreak on *that* other cruise ship, ordinarily it probably would’ve even have been picked up by the news.”
Oceanwide Expeditions, the company behind the Hondius, also received praise online for its communication and transparency in handling the hantavirus outbreak. Three people on the Hondius cruise have died, and the outbreak has prompted precautionary quarantines around the world. One user said they had “no concerns” about an upcoming voyage.
Andrew Coggins, a cruise industry analyst, said this year has been strong for cruise bookings and the hantavirus outbreak was unlikely to change that. “I don’t think people are going to cancel their cruise because they’re worried about hantavirus,” he said. He acknowledged that norovirus outbreaks could be discouraging but said most damaging would be a scenario like the early days of covid, when the virus was new, testing was limited and there was no vaccine.
“Cruise ships are very visible,” he said. “Something happens on a cruise ship, it’s immediately headlines.”
Infectious-disease expert Niranjan emphasized passengers should do plenty of hand-washing, with soap, to help stay healthy on board. But he said he would not be put off cruise travel: “I, myself, have this on my bucket list.”
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