But while you've thought through everything from flight reservations to beach reads, you probably haven't planned how to prevent the one thing that could suddenly and easily ruin your whole trip—getting sick.
Think it won't happen to you? Experts estimate that traveler's diarrhea alone, which is usually contracted via contaminated food or water, affects up to 50 percent of all international tourists for some period of time. Countless others catch nasty bugs from infected insects or simply by using public transportation.
"Traveling without taking some precautions is like driving without wearing a seatbelt," says Dr. Susan McLellan, director of the Tulane University Travel Clinic and associate professor of medicine in infectious diseases at the Tulane University School of Medicine. "You're probably going to be fine—unless something bad happens."
If you'd like to spend your hard-earned vacation abroad seeing more than the inside of your hotel bathroom, before you leave, schedule a trip to a health-care provider who specializes in travel medicine. Aim for two months in advance of your departure date, although even a last-minute visit can offer a lot. You'll get more than a shot in the arm. General education about smart traveling behavior, McLellan says, is one of the most important things a specialist can provide.
For instance, you may already drink strictly bottled water when traveling outside of North America, Northern and Western Europe, Japan, Australia or New Zealand. But it's far more likely, McLellan says, that you'll get a dose of bad bacteria from contaminated food that isn't boiled, cooked or peeled.
Additionally, the more your meal is handled between being cooked and making it to your plate, the higher the risk. That's why you might be better off eating something straight from a street vendor's boiling pot than off a swanky hotel buffet that's been sitting around for a while.
Travelers heading on safari or to exotic, tropical destinations should talk to a doctor and check the Centers for Disease Control and Prevention's Web site to see if mosquito-transmitted diseases, such as malaria or dengue, are a problem, says Dr. R. Doug Hardy, associate professor of infectious diseases at University of Texas Southwestern Medical Center. If so, they might need to take a preventive medication.
Other precautions include regularly applying an insect repellent containing about 30 percent DEET, which will provide hours of protection at a clip. It's also worthwhile to wear long pants and long sleeves; prior to a trip, consider dipping or spraying clothing with the repellent permethrin, McLellan says. Sleeping under a net that's been treated with insecticide is smart too.
For those planning as far out as a trip to the 2008 Summer Olympics in China, experts from The Methodist Hospital Wellness Services in Houston recommend a six-month series of three shots to prevent Hepatitis A and B. They also suggest a typhoid vaccine for people who have adventurous palates or plan to explore beyond the tourist areas.
If you're headed for the high seas or just an afternoon of sailing, prepare to spend time above deck in the fresh air or gazing through a porthole on the horizon to avoid getting seasick. An ailment that can happen to anyone, seasickness is caused by a conflict in sensory input from the eyes and inner ear to a person's balance center. When your ear says you're bouncing around but your eyes say you're standing still, the result is nausea, says Dr. Michael Jacobs, author of "The Comprehensive Guide to Marine Medicine".
Jacobs recommends eating foods that are low in fat to minimize nausea and experimenting with treatments such as ginger root capsules, drugs and pressure bands until you find something that works.
And no matter where you're going, pack the medications you might want access to if you do get a bad headache, cold or gastrointestinal illness. Better to be safe than try to find an all-night drug store in the outback.
"I always bring along what I'm sure I'll need," McLellan says, "and hope I don't need too much else."