One of the biggest misconceptions about cruise ships is that they’re germ incubators—that you can't escape.

But the likelihood of catching a stomach bug on a seven-day voyage is less than 1 percent—which is about a third the risk of getting infected in your day-to-day life back home, says Dr. Carter Hill, a Seattle-area emergency-room physician who specializes in cruise-ship medicine. Here's the catch: If someone onboard does succumb to a nasty virus, it can spread quickly across the ship because it's a closed environment where many people share many things. When a sick passenger with poor hygiene touches a water pitcher, doorknob, or poker chips, other passengers may fall ill, too.

To avoid the flu virus, stomach bug, or any other infectious condition, stick with the following strategies:

1. See a travel medicine specialist before your trip.

Doctor with medical card

Female doctor holding application form while consulting patient (iStock)

If you think a bellyache or throat tickle is unpleasant, you certainly do not want to know what dengue fever feels like. A doctor or nurse specially trained in the area of travel will be tuned into the latest updates for vaccines in the areas you’re docking, and can advise you on what’s recommended and what’s absolutely required.

2. Pack your own hand sanitizer and travel-size disinfectant.



While reputable cruise lines train their staff stringently on cleanliness, it doesn’t hurt to be extra cautious and wipe down especially germy parts of your cabin, such as the phone, doorknob, and remote. You can also compare ships according to how they scored in their latest inspection by the Centers for Disease Control Vessel Sanitation Program, but even the best-scoring ships are vulnerable—all it takes is one highly infectious individual to step on deck and change things.

3. Avoid common serving utensils.



Cruise lines often minimize self-serve buffets for at least the first two days of trip, so that sick passengers can be identified and quarantined before germs spread. Given that passengers can expose themselves to bacterial and viral infections every time the ship docks, the risks continue throughout the trip. To be extra safe, avoid self-serve options entirely. Not an option? If a fellow passenger in front of you in the buffet line offers to pass along a plate or silverware, decline and help yourself to your own.

4. No sharing.

It's almost as sweet as you...

Shot of an attractive young couple sharing a milkshake together (iStock)

Unless you trust whomever you’re traveling with to be as careful as you are, don’t share plates or sample her cocktail. A person can be infectious without showing symptoms.

5. Wash your hands obsessively.


Washing of hands with soap under running water. (iStock)

Rubbing them in warm soapy running water for about 30 seconds is more effective than using sanitizers, says Aron J. Hall, an epidemiologist on the CDC’s viral gastroenteritis team. Dry your hands with a paper towel and use it to turn off the faucet and exit the door. A gel with at least 60 percent alcohol is helpful for on-the-spot use: after using handrails, door handles, and other frequently touched items, like pens, ATM machines, elevator buttons, golf clubs—after all, you never know when you might touch your face and infect yourself without even realizing it.

6. Eat your foods cooked.



You’re likely fine eating salads, fruit, and raw seafood on reputable cruise lines—they have strict guidelines for keeping foods clean—but avoid them when you’re dining on land, particularly in less developed regions. The high cooking temperatures kill off bacteria and viruses that can make you sick; food poisoning is not a fun addition to any cruise.

Check out more tips for staying healthy while cruising.

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