When David Freeman woke up in the middle of the night during a two-week trip to Mexico last month, he knew something was wrong. He felt nauseated and his stomach was making loud rumbling noises.
He managed to ward off illness by taking an antibiotic prescribed by a travel clinic before he left. But even this bit of preparation didn't keep Montezuma's Revenge, also known as traveler's diarrhea, from striking a week or so later.
"It was just like someone turned a hose on inside of you,recalled Mr. Freeman, a 27-year-old, systems programmer from Arnold who had traveled to Ometepec to help build a church.
Mr. Freeman's tale of woe is far from unusual. Every year, thousands of travelers come down with diarrhea, Lyme disease, Rocky Mountain spotted fever and other illnesses. Those who venture overseas run the risk of contracting ailments rarely known in the United States, such as cholera and malaria.
In fact, the likelihood of injury or illness increases greatly wheyou travel, according to William Greenough, a professor of medicine at the Johns Hopkins School of Medicine and a staff member of the school's International Travel Clinic, which prepares people for overseas travel.
"People are much more likely to encounter things that they don'know about when they travel, and to get into trouble with them," explained Dr. Greenough. "You're also under more stress . . . when you're traveling."
Still, you don't have to spend your vacation laid up in your hotel room, especially if you take precautions while traveling in the United States or abroad.
Going overseas, particularly to a developing country, requires more thinking ahead than does travel in the United States. Before leaving, find out everything you can about health risks in the country you'll be visiting, as well as what immunizations are required or recommended.
The Centers for Disease Control in Atlanta has a hot line to answer questions about foreign countries; call (404) 332-4559. Other sources of up-to-date information are doctors or clinics specializing in travel medicine.
Over the past several years, more and more travel health clinics have sprung up around the country -- including at least three in Baltimore -- to advise and treat travelers, particularly those going to developing or tropical countries.
"Most physicians are not aware of all the requirements for traveling in tropical areas," said Dr. Robert Edelman, coordinator of the Travelers' Clinic in the University of Maryland Faculty Practice. "The requirements for vaccinations are changing all the time. . . . If there's an outbreak of meningitis in Africa, we'll know about it but most doctors won't."
Besides giving immunizations, clinic doctors may recommend that overseas travelers get boosters of routine vaccines such as tetanus-diphtheria, polio, measles and influenza, according to Judy Baker, a nurse and the program coordinator at the Hopkins' travel clinic.
The jabs and pills can protect you only so far, however. Avoiding many travelers' ills, such as food poisoning, bacterial infections or malaria, can mean taking precautions from
the time you pick up your toothbrush in the morning to when you get dressed for an evening walk.
Before you even leave for another country, call your health insurance company to see whether your plan will cover your trip. If not, you might want to buy a travel health insurance policy.
Once overseas, reduce your chances of getting diarrhea in developing countries by drinking bottled, boiled or chemically purified water, instead of water from the tap. Refuse ice in your drinks. When brushing your teeth, use bottled water or water from the hot water tap, which has usually been heated to a degree that kills most intestinal bacteria.
In these countries, stay away from vegetables or fruits that have been washed with tap water, as well as from raw or undercooked meat, fish, or shellfish. In South America, cholera has been linked to marinated and raw seafood, so it's probably a good idea to avoid any seafood, according to Ms. Baker.
Getting a cholera vaccination doesn't guarantee your safety, said Dr. Ronald Geckler, director of the International Travel Service at Mercy Medical Center, explaining the vaccine is "not very effective. You can usually avoid cholera by being careful of what you eat and drink."
In the United States, avoid drinking from streams or springs to prevent bacterial infections. Reduce the risk of food poisoning by keeping your perishable food in coolers, which should be stowed in a shady spot. Cover them with a blanket or towel and open only when necessary. When driving, keep the coolers in the car, not the trunk.
If you do get diarrhea, drink plenty of fluids to prevent dehydration. Oral rehydration solution -- available from pharmacies -- can help, said Ms. Baker, adding that you might also treat yourself with an antibiotic, which kills the bacteria that causes diarrhea.