Foreign Travel

Health: The traveler's most valuable possession

When travelers begin to plan a trip, it is common for them to construct a careful itinerary, evaluate how much money will be needed, and to read about the area they will visit. Perhaps they picture themselves walking along ancient byways or examining grand vistas.

No one ever pictures themselves confined to the hotel for days with diarrhea, yet almost half of travelers to developing countries will end up this way if they don't take precautions. Not only will illness wreck a costly trip, but it may also put some travelers in awkward or even dangerous situations. Sometimes, diseases acquired during travel may have prolonged effects on your health or, in the extreme case, may be fatal. Simple precautions taken prior to travel can reduce your risk of illness far away from home.

• Travel to well-developed countries: Travel to tourist areas of Canada, Europe, and other well-developed parts of the world generally doesn't need much preparation-take along a supply of only regular prescription medications and learn how to get health care if you need it. If travel extends beyond the usual tourist routes, or if the traveler has a chronic disease or condition, special precautions may be needed.
• Travel to developing countries: Travel to these countries may pose a greater risk to health. You must take precautions before you go and while you are in foreign countries far different from your own. This discussion is not a complete catalogue of all tropical diseases and is not a substitute for the advice of a knowledgeable doctor. It covers diseases of interest to the routine tourist. Serious adventure travelers will need additional resources.

Preparing for the trip: Travel to a developing country requires careful planning.

• From a health standpoint, most travelers should contact their doctor at least six weeks prior to travel.
• Adventure travelers, those who plan prolonged stays, and those who will leave the usual tourist routes should contact their doctor six months prior to travel.
• Advice may also be obtained from the Centers for Disease Control and Prevention (CDC) or the World Health Organization. Although vaccinations may be recommended or even required for travel to a developing country, no vaccines are required for re-entry into the United States.
• Food and water precautions: Both food and water can be contaminated with bacteria or parasites. Light contamination may not affect the taste or smell of the material but may still cause disease. The usual admonition of "don't drink the water" is good advice in developing countries.
  • Tap water may contain organisms that could cause days of diarrhea or, less commonly, more serious illnesses. Some hotels will provide a carafe of drinking water at the bedside. This is often filled from the tap in the kitchen and is not reliable.
  • Bottled water is usually safe, especially if carbonated. Check the seal on the bottle: Some bottles are re-used and refilled from tap water to be sold to unwary tourists. Boiled water and drinks made with boiled water are usually safe. This includes coffee and tea.
  • Ice is no safer than water. It is usually best to stick with bottled water, boiled water, or sodas.
  • What about brushing your teeth? Basically, use bottled water or no water when brushing your teeth. However, the risk of disease is proportional to the amount of water consumed. So some experts feel that it is all right to brush your teeth with small amounts of (hot) tap water.
  • Foods that are safest are those that are fully cooked and served hot.
  • Fruits that you peel yourself, such as bananas, are usually safe. The exception is watermelon, which may be injected with tap water to increase its weight at market.
  • Human waste (also called night soil) is a common fertilizer in developing countries. Fruits grown near the ground, such as strawberries, are more often contaminated than those grown on trees. Lettuce is also risky for the same reasons. Its crevices are almost impossible to clean, and the water used to do so is often contaminated.
  • Spices do not kill bacteria. Sushi that is so spicy as to burn the tongue is no safer than unseasoned sushi. Shellfish are notorious causes of disease because they are often grown in contaminated water and build up high concentrations of bacteria.
  • It may seem like the prudent traveler's menu is limited. Certainly, prudence must be tempered with practicality. Part of the fun of travel is to experience new dishes. The goal of food and water precautions is to help travelers make informed choices. There is nothing wrong with eating sushi in a developing country if you are aware of the risks and are willing to take them. For many travelers, a little bit of common sense and keeping some medications on hand will result in an enjoyable experience.

• Insect precautions: Insects spread many tropical diseases.
• For most travelers, the biggest insect danger comes from mosquitoes. Travelers to developing countries should carry an insect repellent containing the ingredient DEET. Mosquitoes can spread very serious diseases, including malaria and yellow fever. This is not a time for herbal preparations or mild lotions (such as Skin-so-Soft). Insect repellents should be applied and reapplied according to package directions. Remember that the malaria mosquito bites at night. In malarious areas, wear insect repellent to bed and use mosquito netting if it is available. Room sprays containing permethrin may also be used. For prolonged travel, clothing may be treated with permethrin to serve as a long-term repellent.
• During the day, wear light protective clothing. Long sleeves and pants help reduce the risk of bites. Ticks are also a concern in many developing countries. If traveling in fields or woods, tuck your pant legs into your socks. At the end of the day, check yourself for ticks. The risk of disease increases if ticks are allowed to attach for more than 24 hours. Insect repellents reduce the risk of tick attachment.

• The traveler's medical kit: In developing countries, even simple medical supplies may be hard to find. For this reason, pack some basic supplies.
• Keep prescription drugs in their original bottles. Customs officials are not pleased to see plastic bags full of loose pills. For travelers with complex medical problems, a letter from a doctor or a copy of a recent electrocardiogram may be helpful. If you have one, a copy of your personal health record should be included.
• The American Embassy or Consulate usually will be able to provide a list of doctors who speak English if you need a doctor.

Sex, cars, and drugs: Sexually transmitted diseases, including AIDS, are common in developing countries. The best rule is to abstain from sexual contact with native populations and fellow travelers. Travelers who violate this rule would be wise to carry a supply of condoms.

• Automobile accidents are one of the most common causes of death in travelers. Look both ways before crossing the street, use seatbelts if available, and don't get in the car if the driver is drunk.
• Possession or use of illegal drugs is a very serious offense in most countries. Long prison sentences have been meted out for small amounts of illicit substances.

Travel under special conditions: International travelers often seek adventure.

• Take special precautions when climbing mountains to limit the risk of mountain sickness. Mountain sickness (altitude sickness) can cause headache, nausea, weakness, shortness of breath, and fatigue. In its severe form, brain swelling can cause disorientation, severe headache, bizarre behavior, loss of consciousness, pulmonary edema, or even death. The most effective way to prevent symptoms is to ascend gradually (1,000 feet per day) and to avoid alcoholic beverages and narcotics. Medications are available to reduce the risk of symptoms.
• Scuba diving poses the risk of decompression sickness, such as the bends and puts a strain on the heart. If possible, travelers planning to dive should become certified prior to the trip, because courses at resorts may be shorter and provide less adequate preparation. Divers should follow all safety precautions. People who are out of condition should limit the depth and duration of their dives.
• In general, chronic medical conditions and disabilities do not limit travel if you take sensible precautions. It is best to have a letter from a doctor describing any medical conditions and listing all active medications and doses. If you have one, a copy of your Personal Health Record should be included. Medical insurance may not pay for care abroad. Travelers should contact their insurance carrier to ascertain their degree of coverage and arrange for extended coverage, if desired. Travelers with significant medical conditions should wear medical alert identification bracelets or necklaces.
• Travelers with disabilities may find limited information on accessibility from the Centers for Disease Control and Prevention or the U.S. Architectural and Transportation Barriers Compliance Board. However, information on conditions in foreign countries is limited. In general, it is best to call ahead to ensure the availability of wheelchairs, specially adapted cars, ground-floor rooms, elevators, and other aids. Have a "plan B" in case the promised aids are not available on arrival. U.S. air carriers and cruise lines are required to make reasonable efforts to allow access by disabled persons.
• Pregnancy should not keep you at home unless you have complications from an unstable medical condition, advanced pregnancy, or impending labor.
  • Some activities should be curtailed or eliminated. For example, water skiing and scuba diving pose potential threats to the fetus and should be avoided. Very strenuous activity may cause pre-term labor. Hot tubs should be avoided. Activities that require you to be far from medical care, such as high-altitude hiking, should probably be avoided.
  • Air travel is not advised after the 36th week of gestation and for travelers with impending labor. During flight, it is important that pregnant travelers move around to avoid blood clots from developing and to drink adequate amounts of water or other fluids.
  • Certain vaccines and medications that are normally recommended for travelers might be prohibited during pregnancy. All pregnant women who plan to travel should consult their doctors.
• In general, children should receive protection against the same diseases as adult travelers. All children should be up to date on routine vaccinations. An accelerated vaccination schedule is available for some of the preventive vaccines and may be useful for children who will spend a long period of time in a developing country. Many vaccines are not effective in very young children. Parents should consult their child's doctor for specific information.

The following items are recommended for a traveler's medical kit:

• Prescription medication: Keep it in the original bottle. Keep it in carry-on luggage. Take along more than enough to last the entire trip. It may also be helpful to carry a copy of the doctor's prescription.
• Foot care products: Bring pads to protect blistered feet from further injury. Consider packing athlete’s foot powder if hiking in tropical or damp areas.
• Cold remedies: cough drops, runny-nose remedy, and tissues.
• Diarrhea remedies: Imodium, Lomotil, or Pepto-Bismol. Talk to your doctor about your travel plans and the possibility of carrying an antibiotic. See Traveler's Diarrhea.
• Pain/fever remedies: aspirin, acetaminophen, or others.
• Motion sickness medicine: over-the-counter remedies or prescription medication such as scopolamine patches.
• Insect repellents: They should contain DEET. Also consider insecticide room sprays and mosquito nets. Permethrin may be applied to clothing and bed nets.
• Skin products: Sunscreen (SPF 15 or higher), lip balm, tropical antibiotic ointment, and topical cortisone cream for rashes and bites.
• First aid and miscellaneous supplies: Bandages, adhesive tape, gauze, tweezers, scissors, pocket knife, needle and thread, safety pins, matches, flashlight, sunglasses, thermometer, laxative, toilet paper, and premoistened towelette.
• For women: Bring sanitary napkins/tampons if traveling to developing countries; medication for vaginal yeast infection.

Numerous exotic diseases await those traveling to developing countries, but some simple precautions and vaccines can minimize the risk.

The most commonly acquired disease is traveler's diarrhea. Hepatitis A, a more serious disease, affects very few travelers. Typhoid fever, malaria, yellow fever, and meningitis risks vary based on geographic location visited. The latter diseases are potentially fatal, and the sensible traveler should take precautions against them. Some of these diseases are transmitted by biting insects, others by eating contaminated food or inhaling organisms.

The following list shows ways certain diseases are spread:

• Diseases spread by contaminated food and water: traveler's diarrhea, hepatitis A, typhoid fever, polio, and cholera
• Diseases spread by mosquitoes and other insects: malaria, yellow fever, and Japanese encephalitis
• Diseases spread through coughs and close respiratory contact: meningococcal meningitis, tuberculosis, and influenza
• Disease spread by animals: rabies

Traveler's diarrhea: Diarrhea is among the most frequent health problems encountered by travelers. Because traveler's diarrhea is caused by eating or drinking contaminated food and water, people traveling under primitive conditions are at highest risk.

• The risk of diarrhea varies according to the destination, with the highest risk found in Asia, Africa, and Latin America. Travel to the Caribbean, the Mediterranean, Pacific islands, southern Europe, Israel, and Japan carries a lower risk of diarrhea.
• Many different types of organisms cause traveler's diarrhea. Symptoms vary, but most affected travelers have four to five stools per day for three to four days. Some people have only a few hours of diarrhea. More unfortunate travelers have profuse and frequent stools. Some affected travelers are confined to their rooms, and have to curtail their scheduled activities. High fever, significant abdominal pain, and bloody stools are hallmarks of a more serious type of diarrhea and should cause the traveler to seek medical attention.
• Select food and drink with care. In most cases, the traveler should carry along an antibiotic to take in case diarrhea develops. If diarrhea is mild, bismuth subsalicylate (Pepto-Bismol), loperamide (Imodium), or diphenoxylate hydrochloride (Lomotil) may be taken to slow things down while the antibiotic is working. These medicines should not be taken if bloody diarrhea, severe abdominal pain, or high fever is present.
• It is possible to reduce the risk of diarrhea by taking antibiotics or bismuth subsalicylate daily. However, this approach has its own risks and inconveniences. It should be reserved for the rare traveler for whom even a couple hours of diarrhea would be a serious inconvenience. A physician can advise whether this is appropriate.

Cholera: Although cholera calls up visions of medieval plagues and can be a major cause of anxiety in tourists, it is really very hard to catch. The risk of cholera has been estimated at two cases per million travelers.

• Cholera is a problem in areas where significant amounts of human waste contaminate food or water. The level of contamination must be very high, because a large number of the cholera bacteria must be ingested to cause the disease. This causes the food to smell or taste so bad that few tourists are tempted to eat it. Occasionally, the foul taste is covered with spicy sauces. Raw shellfish have been a source of disease in some areas.
• For the very rare tourist who gets cholera, the good news is that symptoms are usually limited to a few days of diarrhea. If careful attention is paid to drinking fluids, and in severe cases to replacement of salts and sugars, the symptoms go away and do not return. With severe disease, you may have copious watery diarrhea that may exceed 1 liter per hour.
• The cholera vaccine is not very effective. Currently, vaccination is not recommended or required for international travel. In fact, it is no longer on the market in the United States.

Hepatitis A: Hepatitis is an inflammation of the liver. Hepatitis A is found throughout the world and is transmitted primarily when tiny amounts of human waste are inadvertently swallowed. The disease is caused by a virus that attacks the liver.

• Infection is common throughout the developing world. In developed countries, including the United States, community outbreaks still occur.
• Food that is handled by infected workers can transmit the disease to unwary tourists, as can vegetables or fruit grown in human night soil. Risk for infection increases with a longer duration of travel. The risk is higher for those traveling to rural areas and for those who eat and drink in settings with poor sanitation. To decrease this risk, it is important to wash hands frequently and observe food and water precautions.
• Symptoms don't appear immediately. It takes about a month before the sudden onset of fever, fatigue, nausea, and a yellowing of the skin called jaundice. Full recovery may take weeks. Death is rare but does occur. Unlike some other types of viral hepatitis, hepatitis A goes away completely and does not cause chronic disease.
• Protection against hepatitis A is recommended for all those traveling to developing countries. The vaccine is especially important for those who will visit rural areas or eat in local restaurants. Three options exist to protect the traveler from hepatitis A:
• A single dose of the inactivated vaccine in adults is highly effective in preventing disease and provides protection for at least one year. Frequent travelers or those with prolonged stays should get a booster dose at least six months after the first shot. Estimates suggest that the booster shot may protect against hepatitis A for 20 years. The vaccine is not approved for children younger than 2 years.
• Immune globulin, also known as gamma globulin, is very effective in preventing hepatitis A. Unfortunately, the protection lasts only two to five months (depending on the dose). Those traveling with children under 2 years of age and those who are allergic to a vaccine component should consider immune globulin.
• A combined vaccination protecting against both hepatitis A and hepatitis B is available for adults. This vaccination is given in three doses, the same as the regular hepatitis B vaccine schedule.

Hepatitis B: Like hepatitis A, hepatitis B is caused by a virus that attacks the liver. The two diseases have significant differences, however.

• Hepatitis B is transmitted through sexual intercourse, dirty needles used to inject drugs, and contaminated blood transfusions. In addition, the virus can be transmitted when having medical, dental, or cosmetic procedures (including tattooing or body piercing) with needles or contaminated equipment. Hepatitis B is not transmitted through more casual contact such as shaking hands, eating, or drinking.
• Hepatitis B infection occurs throughout the world. The areas with the highest number of people with chronic infection include Africa, Southeast Asia, the Middle East, Pacific Islands, Amazon regions, and certain parts of the Caribbean.
• Once the virus enters the body, the virus begins to attack the liver. It takes an average of four months for symptoms to develop. Symptoms include nausea, vomiting, and abdominal pain. The hallmark of the disease is the yellowing of the skin called jaundice. Death is rare, but does occur.
• Most people can clear their body of the virus after a few weeks, but some adults and a large percentage of infants and children fail to clear the virus and become chronic carriers of the disease. Chronic carriers may develop cirrhosis (irreversible scarring of the liver) or primary cancer of the liver.
• No treatment is available for the acute illness. Medications are available to treat chronic infection.
• Effective vaccines are available to prevent hepatitis B. The vaccine is recommended for those traveling to areas with increased levels of transmission, especially travelers contemplating sexual intercourse abroad, those likely to seek medical and dental care in local facilities, and those providing health care. All unvaccinated children and adolescents in the United States should receive the vaccine. The vaccine is safe and is actually recommended as one of the routine childhood vaccines for U.S. children. Complete protection requires three shots over six months, but even one or two shots offer significant protection. In addition, a combined vaccination is available that offers protection against both the hepatitis A and hepatitis B virus.

Japanese encephalitis: Japanese encephalitis is caused by a virus that is transmitted by mosquitoes. This rare disease exists in much of Asia, but it is very unusual for travelers to contract it. Transmission is more marked in rural areas, in flooded rice paddies, and during wet seasons. Even where the disease is common, very few mosquitoes are infected. The risk to the average traveler is less than one case per million per year. The risk is increased by prolonged stays in infected areas.

• Symptoms include fever, lethargy, and coma. Up to one in five infected people die, and the remainder often have nerve or brain damage.
• An effective vaccine is given as a three-shot series over two to four weeks. The vaccine can cause side effects including arm pain, fever, and even serious allergic reactions. Vaccination should be reserved for long-term (usually more than one month in duration) travelers to Asia with significant exposure to infected areas during appropriate seasons (often May through October). The CDC has listed the important areas and seasons for transmission on their Web site.

Malaria: Malaria is a disease transmitted by the bite of an infected female Anopheles mosquito. Transmission occurs mostly in areas of Central and South America, Haiti, the Dominican Republic, Africa, Asia (including the Indian subcontinent, Southeast Asia, and the Middle East), Eastern Europe, and the South Pacific.

• Fever is the major symptom of malaria. The disease must always be suspected when fever occurs during or after travel to an infected area. In addition, flu-like symptoms can occur, including chills, headaches, muscle aches, and fatigue. The disease may also cause seizures, mental confusion, kidney failure, coma, and death.
• Travelers should observe mosquito precautions that include protective clothing, screened windows, mosquito netting, and insect repellants containing DEET. Currently no vaccine is available, but there are medications that can be taken before, during, and after exposure to prevent the disease. The CDC provides information both via the Internet and through a 24-hour hotline (1-877-FYI-TRIP, 1-877-394-8747) for detailed recommendations on proper medication for the destination and specific prevention tips.
• Several medications are available. The specific type of medication and length of treatment depends on several factors including the traveler's destination. The medicine does not stop the mosquito from biting or the organism from entering the bloodstream. The goal of taking the medication is to destroy the organisms before they have a chance to take hold. Thus, the medications must be continued after leaving the malaria-prone area.

Meningococcal meningitis: Meningococcal meningitis is a bacterial infection of the lining around the brain and spinal cord. The bacteria are transmitted from person to person through respiratory secretions spread through coughing, sneezing, and oral secretions.

• The disease occurs sporadically in clusters throughout the world. However, the most significant outbreaks occur in sub-Saharan Africa, known as the "Meningitis Belt," extending from Senegal to Ethiopia and recently extending further south into the Great Lakes regions. Transmission is higher in the dry seasons. Those traveling to the meningitis belt during the dry season should be advised to receive the vaccine.
• During the Hajj, the annual pilgrimage to Mecca, Saudi Arabia hosts thousands of wayfarers from all over the world. Crowded conditions and arrivals from the infected zone of Africa combine to create the potential for an epidemic. Due to an outbreak associated with the 1987 Hajj, Saudi Arabia requires that Hajj and Umrah visitors have a certificate of vaccination before entering the country.
• Symptoms of meningitis include sudden onset of fever, intense headache, stiff neck, nausea, and vomiting. Other symptoms may include confusion or coma. This disease is potentially fatal and should be considered a medical emergency.
• Meningococcal meningitis can be treated with a number of effective antibiotics. Vaccination is not required for entry into any country except Saudi Arabia, for those traveling to Mecca during the annual Hajj and Umrah pilgrimage.
• The bacteria that cause meningococcal meningitis have developed into five slightly different strains, known as serotypes. Currently two vaccines are available. One has been available since 1981, and the other, thought to provide better and longer lasting protection, was licensed in 2005. The newer vaccine is also thought to be better at preventing the disease from spreading from person to person. Both vaccines can prevent four strains of the disease, including two of the three most common in the United States and one type that causes epidemics in Africa. Travelers should check to see if the vaccine is recommended for their destination and receive the vaccine at least one week before departure.

Plague: Plague is caused by a bacteria called Yersinia pestis and is typically transmitted when people are bitten by fleas or rodents. It has gained attention in recent years as a potential weapon of bioterrorists. Transmission usually requires close contact with rodents in a rural area. Only a handful of cases have been reported in American travelers in the last century. Due to the very low risk of disease, plague is not a concern for the routine traveler. No vaccine is available. Travelers who will live or work in close contact with rodents, such as field biologists, may consider taking daily doxycycline to reduce the risk of disease.

Plague can rarely be spread via respiratory secretions when a person with plague pneumonia coughs. However, such infections are seen only in epidemic situations and are more of historical interest than posing a real threat to the modern traveler.

Polio: Although vaccination has eliminated naturally occurring polio in North and South America, rare cases continue to occur in developing countries of Africa, the Middle East, Afghanistan, and Pakistan. The disease is caused by a virus that is spread when human waste is inadvertently swallowed. Symptoms include muscle aches and paralysis. Many infected people never have any symptoms. Travelers to infected areas should be immune to polio. For most adults who have already been vaccinated in the remote past, this means a single vaccine booster dose of the injectable vaccine before travel.

Rabies: Rabies is spread through contact with infected secretions, often from a bite wound from an infected animal. Infected saliva can spread disease into open cuts. In caves, disease may occur when bat guano is aerosolized and inhaled. Dogs, cats, skunks, raccoons, bats, cattle, and foxes are among animals that can transmit rabies.

• Rabies is caused by a virus that works its way into the brain over days to months. Once there, the virus causes coma and is virtually always fatal. Travelers at high risk include veterinarians, spelunkers (cave explorers), and those who will handle wild animals. Travelers should avoid petting, touching, or playing with animals in developing countries.
• Travelers to developing countries who will not have access to medical care for prolonged periods should consider vaccination.
• Bite wounds should be cleaned immediately with soap and water. Unless there is a way of ensuring that the animal is free of rabies, the bitten traveler should be evaluated by experienced medical personnel and will require vaccination to prevent rabies from occurring. Although the vaccine available in the United States is relatively safe, vaccines available in developing countries may cause significant side effects. Further, the cleanliness of needles used for injection may be a concern. In most cases, evacuation to a developed country for vaccination is recommended even if this would delay vaccination by a few days. Sometimes, an injection of rabies antibodies is also needed. Even travelers who have been vaccinated in the past need to be evaluated and often vaccinated after bite wounds.

Typhoid fever: Typhoid fever is a bacterial infection of the intestinal tract and blood stream. It is spread by contaminated food and water. The bacteria are passed in the feces and urine of those infected. Therefore, infection can occur by eating food handled by someone who has not washed their hands after using the bathroom or by drinking water directly contaminated by sewage containing the bacteria.

• Regions affected include the Indian subcontinent and other developing countries in Asia, Africa, the Caribbean, and Central and South America. There are approximately 22 million cases worldwide. Approximately 200-300 cases are reported annually in the United States, mostly among travelers.
• Fever is the hallmark of the disease. Headache, weakness, stomach pains, diarrhea, and loss of appetite can occur. Some people may develop a rash of flat, rose-colored spots that usually disappears in three or four days. Although most people clear the bacteria from their system, a few may appear to recover but still shed the bacteria in their stool. These carriers feel fine but can inadvertently spread the disease to others.
• Antibiotic therapy is the only effective treatment for typhoid fever. Supportive measures, including fluids, medications to bring down fevers, and appropriate nutrition are also important.
• Frequent hand washing is recommended, as are food and water precautions.
• Two new typhoid vaccines are available. One is a capsule by mouth requiring a booster every five years and the other is an injection with a booster recommended every two years. Both vaccines are safe and effective. Vaccines need to be completed at least one week before travel.

Yellow fever: Yellow fever is a viral infection that is spread by mosquitoes. The disease occurs in sub-Saharan Africa and South America. It has never been documented in Asia. The CDC provides current information about which countries and regions are affected.

• People who are infected get fatigued, become feverish, and their skin turns yellow. A small number die. The diagnosis can be confirmed by blood tests. No specific treatment is available for yellow fever.
• Those traveling to at-risk areas should take general precautions against exposure to mosquitoes. Wearing long-sleeved shirts and long pants, using insect repellents containing DEET on exposed skin and permethrin-containing repellents on clothing, and staying in screened-in and air-conditioned areas can reduce mosquito bites. However, the vaccination is the most important measure for protection, and therefore it is important to contact a health-care provider at least two weeks before travel to determine if the vaccination is recommended.
• The yellow fever vaccine is a safe and effective vaccine that can only be given at authorized yellow fever vaccination centers. Protection occurs in 95% of those who receive the vaccine and takes place within one week. After one dose, protection lasts for 10 years. Those traveling to areas at risk should talk to their health-care provider before receiving the vaccine. Vaccination is sometimes required before travelers are permitted to enter selected countries. Some countries require vaccination only if the traveler is coming from an infected area. The United States is not an infected area. An International Certificate of Vaccination, stamped by an official vaccinating center, affords proof of vaccination. In the United States, the CDC is responsible for licensing official vaccination centers. The official vaccination certificate is good for 10 years.

Other immunizations and diseases: A visit to a doctor for travel-related vaccines is a good time to make sure your routine vaccines are up to date.

• In the United States, tetanus boosters are recommended every 10 years.
• People born after 1956 should make certain that their measles vaccines are up to date. Older people are usually assumed to have had measles as children.
• Influenza occurs in the winter season in temperate areas and year-round in the tropics. Vaccination should be considered in travelers aged 50 years and older and in persons with chronic medical conditions.
• Tuberculosis has a worldwide distribution. Long-term travelers may want to consider getting a skin test prior to departure. Travelers with negative skin tests should have a repeat test after returning. The BCG vaccine is of uncertain value and is neither recommended nor available in the United States.

The following are general recommendations. Specific recommendations depend on the travel itinerary and the medical history of the traveler.

Diseases to Consider When Traveling to Specific Areas

* Outbreaks may occur in other areas as well.

All travelers should follow food and water and insect precautions. These diseases may be limited to selected locations or countries within the above areas. This is not a comprehensive listing of all possible diseases. Please consult your physician to receive recommendations specific to your travel itinerary.

• Africa: Travelers should be up to date on routine vaccinations, such as tetanus. Hepatitis A vaccine and typhoid vaccine are recommended. The CDC recommends updating polio immunizations. Yellow fever vaccine is recommended for travel to infected areas and may be required before admission to some countries is allowed. Meningococcal meningitis occurs in much of sub-Saharan Africa. Malaria exists in most countries. Consult the CDC Web site to determine if your travels will bring you into contact with malaria. Long-term travelers and health-care workers should consider hepatitis B vaccination. Rabies vaccine is recommended for long-term travelers and people, such as veterinarians, who will handle animals.
• Asia and the Middle East: Travelers should be up to date on routine vaccinations, such as tetanus. The hepatitis A vaccine and typhoid vaccine are recommended for travelers to developing countries and rural areas. The CDC recommends updating polio vaccinations. The meningococcal vaccine is recommended for pilgrims to Saudi Arabia. Proof of immunity may be required during the Hajj and Umrah pilgrimages before entry to Saudi Arabia is permitted. A risk of malaria exists in selected areas. Long-term travelers and health-care workers should consider hepatitis B vaccination. The rabies vaccine is recommended for long-term travelers and people, such as veterinarians, who will handle animals. The Japanese encephalitis vaccine is recommended for travelers who will have prolonged exposure to rural areas in infected zones. Yellow fever does not occur in Asia, but travelers who have recently visited South America or Africa may be required to show proof of immunity.
• Eastern Europe and the former Soviet Union: Travelers should be up to date on routine vaccinations such as tetanus. The risk of hepatitis A, typhoid fever, and polio increases as political systems break down and sanitation declines. Malaria exists in limited areas not visited by most travelers.
• Oceania: Travel to Australia and New Zealand does not require special immunizations or medications. Other countries may harbor tropical illnesses. Malaria occurs in Papua New Guinea and some surrounding islands. People who may travel under unsanitary conditions, those who plan to eat in local restaurants, and those who travel to developing countries should consider hepatitis A vaccination and typhoid vaccination. Long-term travelers and health-care workers should consider hepatitis B vaccination. Rabies vaccine is recommended for long-term travelers and people, such as veterinarians, who will handle animals.
• South America and Central America: Travelers should be up to date on routine vaccinations, such as tetanus. The hepatitis A vaccine and typhoid vaccine should be considered for most travelers. The yellow fever vaccine is recommended for travelers to selected areas and may be required before admission to some countries is allowed. A risk of malaria exists in some countries. Long-term travelers and health-care workers should consider hepatitis B vaccination. The rabies vaccine is recommended for long-term travelers and people, such as veterinarians, who will handle animals.

• International Society of Travel Medicine
• American Society of Tropical Medicine and Hygiene — for a listing of clinics in your area
• Centers for Disease Control and Prevention (CDC), National Center for Infectious Diseases, Traveler's Health
• World Health Organization, International Travel and Health
• Travel Health Online