For general travel health information, details on current disease outbreaks, and the most current shot recommendations for different areas of the world, see:

• The U.S. Centers for Disease Control and Prevention (CDC) Web site at www.cdc.gov/travel.
• The World Health Organization (WHO) Web site at www.who.int/en.

Preparing for a journey takes planning and time. Proper planning is the best way to stay healthy during your trip. See a doctor at least 6 weeks before you go so that you'll have time for immunizations and other health precautions you may need to take in advance. Better yet, talk to your doctor as soon as you know you will be traveling. There are some shots that need to be given more than once, and you may need more than six weeks in some cases. There are several factors to consider in preparing for a trip.

Your individual health needs

If you have any chronic diseases or other health concerns, such as birth control or allergies, see your doctor. You may need to adjust your itinerary to accommodate your health needs. For example, if you have heart failure or a history of blood clots, you may need to take shorter flights with more stops to avoid long periods of sitting. If you have asthma, chronic obstructive pulmonary disease (COPD), or other lung diseases, you may need to avoid stays in polluted cities or at high altitudes.

Evaluate whether you will be physically able to meet the rigors of your particular trip. Most travel, even if you are going on a professionally led tour, typically demands more physical effort than is required at home. Boost your fitness by starting an exercise program, such as fitness walking, in advance.

If you have health problems, carry a letter from your doctor describing your conditions, a list of your routine medications including their generic names, and written prescriptions for refills if you will be gone long. People with heart conditions should travel with a copy of their most recent electrocardiogram (EKG, ECG) for comparison should they have chest pain or other symptoms. If you have diabetes, you can take precautions to prevent problems while traveling.

Leave your prescription medications in the original containers-your name must match the name on the bottle-and pack them in a waterproof container in your carry-on luggage. Take extra amounts of your routine medications packed in checked luggage in case of theft or loss.

If you are pregnant, talk to your doctor before making any travel decisions. If you decide to travel, take some general precautions while traveling, such as notifying the airline of your condition before you fly and taking occasional walks while on a long flight to increase the blood circulation in your legs (good advice for all travelers).