Sailing Into Sickness?

Medically Reviewed by Brunilda Nazario, MD
5 min read

Cruising should be as good as it gets. Exotic destinations. A party atmosphere. Food feasts galore.

But there's been trouble in paradise in recent months. Highly publicized outbreaks of gastrointestinal illnesses have left many cruisers sprinting for bathrooms that weren't supposed to be part of their itinerary. Newspaper headlines have blared the names of highly contagious bugs - most notably, the Norwalk virus - that most people had never heard of. And for anxious travelers who once thought of cruise ships as a welcome oasis from the fears and hassles of airline travel, they're now thinking twice, or at least taking a few more precautions before they stroll up the gangplank.

Of course, a little perspective is in order. More than seven million people took cruises out of North American ports in 2002, and most of them returned home with splendid memories and enough photographs to bore their friends and neighbors for months. But for the relatively small percentage whose voyage was sabotaged by a queasy stomach and diarrhea , they probably wish they had stayed on solid ground and close to home.

"Given the millions of people who go on cruise ships every year, outbreaks are not a real frequent occurrence, but they do seem to be increasing," says David Freedman, MD, director of the Travelers Health Clinic at the University of Alabama at Birmingham. "The data appear to suggest that there have been at least three times as many recent outbreaks of diarrheal disease on cruise ships, as compared to a year ago."

Nevertheless, you may be able to sail past any perils lurking at sea with a little knowledge of what you may encounter and the ways to avoid it.

Outbreaks of the Norwalk virus and other infections really shouldn't be a surprise. After all, says Aaron Glatt, MD, cruise ships can become something of a breeding ground for these microorganisms, quickly spreading from one person to another in the confined space and close living quarters of an oceangoing vessel populated by hundreds and even thousands of people. When these bugs strike, the result can be 24 to 48 hours of misery: nausea, vomiting, diarrhea, low-grade fever, and abdominal pain. It's not exactly what the travel brochures promised.

"If you have a Norwalk infection, and you're walking around on dry land, you probably won't infect a lot of people, whereas in a closed space like a cruise ship, it's easy to spread a very hardy virus like this one," says Winnie Ooi, MD, director of the Travel and Tropical Medicine Clinic at the Lahey Clinic in Burlington, Mass. "Because there are a lot of common areas on the ship that people move through, outbreaks can certainly occur."

The Norwalk infection and various respiratory illnesses (like the common cold and flu) are the most common afflictions that can rise to the surface on cruise ships, but bacterial ailments may become problematic as well. Organisms such as salmonella, shigella and E. coli have caused recent outbreaks of diarrhea on ships, and fall into the grab-bag category of "traveler's diarrhea."

In a recent cluster of gastrointestinal illnesses on a cruise ship sailing from Tenerife to the U.S., salmonella was identified as the likely culprit. Most often, these bacterial infections are food-borne, and are a consequence of a breakdown in sanitation measures in the ship's kitchen, says Freedman.

Seasickness is uncommon on large cruise ships because of their size. "However, some ships do go through rough waters, like around the tip of South America," says Mark Wise, MD, a family physician and travel medicine specialist in Toronto, and author of The Travel Doctor.

For people who may be susceptible to motion sickness, Wise suggests not overeating, staying away from cigarette smoke, and talking to your physician about using a skin patch containing a medication called scopolamine, often applied behind the ear.

Medical problems such as sexually transmitted diseases, often arising from casual sexual encounters, are not unusual among tourists, including those on cruises. Alcohol use can decrease judgment, says Freedman, and people can lose their inhibitions once they're away from home and on vacation

Particularly in light of recent Norwalk virus outbreaks, cruise company executives say they're working hard to stay one step ahead of the next onboard epidemic. According to a statement from the International Council of Cruise Lines, "The cruise industry is committed to providing a safe, healthful environment for all passengers at sea."

In recent months, several ships that have experienced infectious outbreaks have been docked for at least a week for thorough disinfecting. But for most cruise ships, which often leave with a new load of passengers just hours after the last group has disembarked, onboard housecleaning must be done in the limited time between sailings.

"There may be only three to four hours to clean the ship between cruises," says Ooi. "And given that the Norwalk virus is so hardy, if the cleaning crew doesn't do a really good job of cleaning the common areas, the virus can maintain a foothold."

Yet even the most heroic ship disinfections are no guarantee of a bug-free cruise, says Dean Cliver, PhD, professor of food safety at the University of California, Davis, and head of the World Health Organization Collaborating Center for Food Virology. "If the next group of travelers comes aboard with a substantial number of infected people, this can cause an outbreak all over again," he says. "And it's very hard to conduct ongoing disinfections while passengers are onboard."

To protect yourself on cruises, the best advice may be the simplest: Wash your hands frequently and thoroughly. "Use warm water, soap, and at least 20 seconds of rubbing," suggests Cliver.

Many cruise lines are now advising their passengers to minimize handshaking and other personal contact with fellow passengers and crew members in order to avoid the transmission of viruses. Also consider becoming a little more careful in the ship's dining room in order to avert foodborne infections. As Wise says, "I joke that I used to tell people to eat on the ship and not on the land - and now I tell them the opposite!"

Wise adds, "I'm certainly not at the point of telling people to abandon the lovely shrimp, scallops, and salads on ship. But if you want to be a little selective, you might eat everything except the uncooked seafood, which does pose a higher risk."

When packing your suitcase for a cruise, think about bringing along some Dramamine (dimenhydrinate), which can be helpful for motion sickness. Imodium (loperamide) can reduce diarrheal symptoms.

"The main treatment for diarrhea is fluid replacement," advises Wise. For children, there are ready-made electrolyte solutions such as Pedialyte."

Most cruise ships sail with a physician onboard. "People shouldn't be self-medicating," advises Glatt, chief of infectious diseases at Saint Vincent Catholic Medical Centers in New York . "See a physician in advance if you're going into a situation where you may have an increased risk of illness."