Thailand poses no specific health hazard that requires immunization, but the same cautions for visiting rugged, tropical climes applies to the more remote areas of the Thai kingdom. Most health-care professionals in the West are able to supply you with information about health problems specific to the region, and it is recommended that travelers have current immunizations for Hepatitis A and Tetanus. Heat and humidity combined with sometimes less sanitary conditions than most are used to in their home countries means that it is important to watch for infections; wash any wound promptly and keep covered.

General Availability of Health Care--Dispensaries and hospital facilities in Thailand, especially in urban centers, are on par with most of the west and even the smallest towns will have some tenable facility or provide transport to a good hospital. Many Thai doctors and health-care professionals receive training abroad, and, in fact, places like Bumrungrad Hospital (tel. 02667-1000; www.bumrungrad.com.) in Bangkok and the better facilities in Phuket have given rise to a unique phenomenon of "medical tourism,", where visitors take care of medical problems, anything from dental work to plastic surgery, and, because of the affordability of medical care in Thailand (and at the same high standard of quality) are able to combine their recovery with a beach vacation or enjoy the comforts of big-city Bangkok in the process.

Common Ailments

Stomach Trouble -- Don't drink the water and watch what you eat. The most common illness in these parts is diarrhea. Often, just the abrupt change in climate and diet bring on an uncomfortable bout of Montezuma's Revenge that takes all the fun out of touring temples or riding rural buses. It's a good idea to bring with you a good over-the-counter antidiarrhea medicine such as Imodium A.D., an electrolyte supplement to mix in plenty of water (to prevent dehydration and loss of energy), and, above all, a roll of toilet paper or packet of tissues for while you're away from your hotel. Don't count on public toilets having any. Some cases of diarrhea are caused by bacteria or viruses in either food or drinking water. Be sure to stick to canned or bottled drinks or the bottled water sold everywhere. While food in most restaurants is perfectly safe, be wary of street food. If you eat from a street stall, check ingredients for freshness and cleanliness. Watch the cook prepare food before you and never eat anything that looks like it's been sitting around. Avoid anything raw -- vegetables included -- from vendors. If your condition lasts for more than 24 hours and you have painful cramps, chances are you've picked something up and should find a doctor for possible antibiotic treatment.

Tropical Illnesses -- Hepatitis A can be avoided using the same precautions for diarrhea. Most Asians are immune through exposure, but people from the West are very susceptible. Talk to your doctor about receiving a vaccine before your trip.

Major tourist areas such as Bangkok, Phuket, Ko Samui, and Chiang Mai are malaria free. However, malaria is still a problem in rural parts, particularly territories in the mountains to the north and near borders. Don't bother with prophylactic tablets like chloroquine; they don't work here. The only solution is to cover up with long pants and sleeves after dark, stay indoors, sleep with mosquito netting, and use repellents. Make sure your repellent is specially made for the tropics. DEET works well, but it is a toxic chemical, so you may want to find a spray with low concentrations. If, despite these precautions, you develop a fever within 2 weeks of entering a high-risk area, be sure to consult a physician.

Dengue fever is a problem throughout Southeast Asia, and recent years have seen epidemics in the region. Similar to malaria, the virus is spread by mosquito bites, but the mosquitoes that carry the virus only bite during the day. There is no existing prophylactic, so like malaria your best bet is to avoid being bitten. Symptoms include fever, a skin rash, and severe headaches. Seek medical attention. For foreign visitors, the disease is rarely fatal, but for people who are native of endemic areas, the internal hemorrhaging caused by the virus often kills.

Japanese encephalitis is a viral infection that attacks the brain and is spread by mosquito bite. Outbreaks have been known to occur in the region, so stay abreast of the most up-to-date CDC information. Like malaria and dengue, the best protection is to avoid being bitten.

Bug Bites & Other Wildlife Concerns -- One of the biggest concerns, as you can see from the list of tropical diseases above, are mosquitoes. Take appropriate precautions. It's not a bad idea to wear long trousers instead of shorts (also more acceptable in Thai culture) as protection against not just mosquito bites, but ticks, snakes and other pests, as well as to spare yourself cuts and scrapes that can get infected, most important when on jungle treks. Do not get creative about nibbling bush-tucker, even if you think you know what kind of mushroom it is, because there are some real nasty ones in this part of the world. When venturing into thick jungle terrain, do so with a qualified guide, of course, and keep an eye out for the many creepy-crawlies: it's a jungle out there.

Rabies is a concern in Thailand as are bites from any stray dogs, infected or not. You'll see some pretty miserable canines in your travels in Thailand -- sick and diseased, sleeping on the side of the road, limping through markets, hanging around temple complexes where monks do their karmic duty and feed the animals (though never care for them beyond that). Occasionally, a rabid animal makes its way into the mix. Stay clear of stray dogs, and find a doctor fast if you've been bitten. The sooner you receive treatment, the better. All Thai dogs have been whacked with sticks and hit by flying rocks so even miming those actions is often enough of a deterrent.

Don't swim in freshwater streams or pools (other than chlorinated hotel pools), as they are frequently contaminated. Avoid the ocean near the outlets of sewage pipes and freshwater streams, because of contaminated water -- poisonous sea snakes often inhabit these areas. Be especially careful of coral reefs (such as those along Phuket), jellyfish, and sea urchins, and treat all cuts or stings immediately by washing with soap and water and applying an antimicrobal preparation. Antihistamines can help with allergic responses. Ear infections are a common problem; those prone to ear infections can use mild boric acid or vinegar solutions to prevent or combat them.

Coping With the Heat -- Avoid sunstroke or heat exhaustion by exercising caution when getting active out in the roasting sunlight. Thailand's slower pace of life is in fact dictated by the hot and humid weather so (when in Rome) take it easy, stay out of the noon-day sun, and drink lots of liquid to avoid dehydration. Bottled water is inexpensive and widely available. Avoid excessive exposure to the sun, use a strong sunscreen, and wear a hat for protection. Restricting alcohol consumption and eating light meals will help you to acclimate.

What to Do If You Get Sick in Thailand

Medical services in Thailand are good, and over-the-counter dispensaries are comparable with standards in the West. Most offer prescription drugs on an as-needed basis, the pharmacist more or less acts as a diagnostician in many parts. In an emergency, do not hesitate to contact your county's embassy. In most cases, your existing health plan will provide the coverage you need. But double-check; you may want to buy travel medical insurance instead. (See the section on insurance, above.) Bring your insurance ID card with you when you travel.

If you suffer from a chronic illness, consult your doctor before your departure. For conditions like epilepsy, diabetes, or heart problems, wear a Medic Alert Identification Tag (tel. 800/825-3785; www.medicalert.org), which will immediately alert doctors to your condition and give them access to your records through Medic Alert's 24-hour hot line.

Pack prescription medications in your carry-on luggage, and carry prescription medications in their original containers, with pharmacy labels -- otherwise they won't make it through airport security. Also bring along copies of your prescriptions in case you lose your pills or run out. Don't forget an extra pair of contact lenses or prescription glasses. Carry the generic name of prescription medicines, in case a local pharmacist is unfamiliar with the brand name.

Contact the International Association for Medical Assistance to Travelers (IAMAT) (tel. 716/754-4883, 416/652-0137 in Canada; www.iamat.org) for tips on travel and health concerns in the countries you're visiting and lists of local, English-speaking doctors. The United States Centers for Disease Control and Prevention (tel. 800/311-3435; www.cdc.gov) provides up-to-date information on necessary vaccines and health hazards by region or country. Any foreign consulate can provide a list of area doctors who speak English. If you get sick, consider asking your hotel concierge to recommend a local doctor -- even his or her own. You can also try the emergency room at a local hospital; many have walk-in clinics for emergency cases that are not life-threatening. You may not get immediate attention, but you won't pay the high price of an emergency room visit.