CHAPTER 320
Travel and Health
Travel preparation is crucial, even for healthy people. Proper preparations are inexpensive relative to the costs of getting sick or injured while away from home.
Travel Kits
Travel kits containing first-aid supplies, pain relievers (such as acetaminophen or nonsteroidal anti-inflammatory drugs), decongestants, antacids, antibiotics, and loperamide for traveler’s diarrhea are useful for minor injuries and illnesses. Also, topical drugs, such as hydrocortisone 1% cream, an over-the-counter antifungal cream, and an antibiotic ointment, should be considered. Travelers should carry their travel kit, prescription drugs, extra eyeglasses or other corrective lenses (as well as a current written prescription for either), and hearing-aid batteries in a carry-on bag in case their checked baggage is delayed, lost, or stolen. Major problems can often be prevented with common-sense precautions.
Health and Travel Insurance
Health insurance is important for travelers. Even with domestic travel, some plans limit coverage for health care away from home. Thus, travelers should know the limitations of their policies.
Coverage is more often a problem for international travel. Some domestic insurance plans limit coverage for vaccinations and preventive drugs for international travel, even though some vaccinations are required for entry into certain countries. Likewise, Medicare and most commercial health insurance plans do not cover the cost of any treatment given outside the United States. In addition, a cash deposit or payment in full may be required in international hospitals before care is provided.
To avoid high costs or inability to obtain care, travelers should determine in advance what international coverage, if any, their health plan offers, how to seek prior authorization for international care, and how to make a claim after an emergency. Travel health insurance, including insurance for emergency evacuation, is available through many commercial agencies, travel services, and credit card companies. Travelers may want to purchase insurance for services such as emergency care, transportation for care within foreign countries, transportation back to the United States for care, medical equipment and personnel during transport, dental care, prenatal or postnatal care, lost or stolen prescription drugs, and medical translators.
The International Association for Medical Assistance to Travellers (IAMAT), a nonprofit organization, maintains a list of English-speaking doctors in cities around the world (www.iamat.org). Other directories listing English-speaking doctors in foreign countries are available from several organizations and web sites (see page 2164). United States consulates may help travelers identify and secure emergency medical services.
Vaccinations
Vaccinations are important for travel to most developing countries and are required by some countries for entry. Ideally, travelers should visit their usual
VACCINES FOR INTERNATIONAL TRAVEL* †‡
| INFECTION | REGIONS WHERE THE VACCINE IS RECOMMENDED | COMMENTS |
| Hepatitis A | Throughout the developing world | Two doses are given at least 6 months apart. Protection is full after the first dose for 6-12 months and after the second dose for life. |
| Hepatitis B | Throughout the developing world (hepatitis B is particularly common in China) | This vaccine is recommended for extended-stay travelers and all health care workers. |
| Influenza | Year-round in the tropics, between October and April in the Northern hemisphere, and between April and September in the Southern hemisphere | This vaccine is recommended for adult travelers to these destinations and for people traveling to any destination in large groups. |
| Japanese B encephalitis | Rural areas throughout most of Asia, particularly in areas with rice and pig farming | Three doses are given over 28 days. |
| Meningococcus | Northern Sub-Saharan Africa from Mali to Ethiopia (the meningitis belt) | Risk is higher during the dry season (December through June). This vaccine is required for entry into Saudi Arabia during Hajj or Umrah. |
| Rabies | All countries, including the United States | This vaccine is recommended for travelers at risk of animal bites, including rural campers, veterinarians, and field workers. It does not eliminate the need for additional vaccinations after an animal bite (for added protection). |
| Typhoid fever | Throughout the developing world, especially in South Asia (including India) | Two forms of the vaccine are available. Single injection form: It protects for 2 years and is safe for pregnant women. Pill form: One pill is taken every other day for a total of 4 pills. This form protects for 5 years and is not safe for pregnant women. |
| Yellow fever | Tropical South America and tropical Africa | The disease is rare, but many countries require vaccination for entry. This vaccine is not safe for pregnant women. |
| *See also the Immunization chapter on page 1144. | ||
| †In addition to the listed vaccinations, travelers should be up to date on vaccinations for measles, mumps, rubella, tetanus, diphtheria, polio, pneumococcal disease, and varicella. | ||
| ‡All recommendations are subject to change. For the latest recommendations, consult the Centers for Disease Control and Prevention (www.cdc.gov). | ||
health care practitioners at least 6 to 8 weeks before their travels. An International Certificate of Vaccination is the best place to document the names and dates of all vaccinations. The certificate is easy to carry and can be obtained from many travel clinics or from the Superintendent of Documents at the U.S. Government Printing Office.
Traveling With Medical Conditions
Traveling with a medical condition requires special preparation. People with a medical condition should visit their doctor before departure to ensure that their condition is stable and to determine whether any changes in drugs are needed. Detailed written medical information, including information about vaccinations, drugs, results of major diagnostic tests, and types and dates of treatments, may be the most valuable thing a person can have in a medical emergency. People should consider asking their doctor to prepare such information in a letter. Medical identification bracelets or necklaces are essential for people with conditions that can cause rapid, life-threatening symptoms, confusion, or unconsciousness (such as diabetes, seizures, and severe allergic reactions). Travelers should also carry proof of medical insurance. Travelers with heart disorders should travel with a copy of a recent electrocardiogram (ECG).
Drugs should remain in their original bottles so that the precise names of the drugs and the instructions for taking them can be reviewed in an emergency. The generic name of a drug is more useful than its brand name because brand names differ among countries.
Travelers should also pack an extra supply of drugs in carry-on bags in case checked bags get lost, stolen, or delayed in transit or the return trip is delayed. Because opioids, syringes, and large amounts of any drug are likely to raise the suspicions of security or customs officers, travelers should have a doctor’s note explaining the medical need for the supplies. In addition, syringes should be packed together with the drugs that are dispensed in them. Travelers should also check with airports, airlines, or embassies to determine what additional documentation is helpful in making travel with these supplies go smoothly.
Problems in Transit
Several conditions are common even among healthy people while in transit.
Motion Sickness
Motion sickness during air, sea, rail, bus, or car travel occurs when the brain receives conflicting signals about movement (see page 663). Motion sickness is often triggered by turbulence and vibration and made worse by warmth, anxiety, hunger, or overeating. The main symptoms are stomach upset, nausea, vomiting, sweating, and dizziness (vertigo).
Motion sickness can be minimized by the following:
Moderating intake of food, fluids, and alcohol (before and during travel)
Fixing the eyes on a stationary object or on the horizon
Lying down and keeping the eyes closed
Choosing a seat where motion is felt least (for example, in the center of an airplane, over the wing)
Refraining from reading
Sitting by an open window or an air vent if possible
A cabin in the middle of a ship close to water level may reduce motion sickness in some people. A scopolamine patch (which requires a prescription) or nonprescription (over-the-counter) or prescription antihistamines are often useful, especially if taken before travel. However, these drugs often cause drowsiness, light-headedness, and dry mouth and can result in confusion, falls, and other problems in older people.
Blood Clots
Blood clots can occur when people sit for long periods during air, rail, bus, or car travel. Blood clots (deep vein thrombosis—see page 433) are more common in people who
Are older
Are overweight
Smoke cigarettes
Have varicose veins
Are taking estrogen
Are pregnant
Have recently had surgery
Have had blood clots
Have been inactive or immobile
Blood clots form in leg or pelvic veins and occasionally dislodge and travel to the lungs (called pulmonary emboli—see page 488). Some blood clots in the legs do not cause symptoms, whereas others cause cramping, swelling, and color changes of the calves and feet. Pulmonary emboli are much more serious than blood clots in the legs. People may first develop a sensation of not feeling well, followed by shortness of breath, chest pain, or fainting. Pulmonary emboli are sometimes fatal.
The risk of developing blood clots can be reduced by changing positions frequently, straightening and moving the legs frequently while seated, drinking enough fluids, and getting up to walk and stretch every 1 to 2 hours. Prolonged leg crossing may decrease leg circulation and should be avoided. Avoiding caffeine and alcohol and wearing elastic support stockings also reduce risk.
Ear and Sinus Pressure
Ear and sinus pressure while flying is the result of changes in air pressure in the airplane (cabin pressure). Normally, as an airplane takes off and climbs (ascends), cabin pressure decreases, and small pockets of air trapped in the sinuses and middle ear expand, leading to ear pressure, ear popping, or both and to mild sinus pressure or discomfort. As an airplane descends, ca-bin pressure increases, and similar symptoms occur. These mild sensations usually disappear as air pressure in the sinuses and ears equalizes with cabin pressure. Untreated dental problems or teeth that were subjected to recent dental procedures may also become painful when air pressure changes.
Swallowing (particularly while holding the nose closed) frequently or yawning during ascent and descent helps equalize pressure. Some people suck on hard candies during descent. These actions are normally sufficient to relieve minor ear and sinus discomfort. With allergies, sinus problems, and head colds, however, the passages that connect the ears and sinuses to the nose and mouth become inflamed and sometimes blocked by mucus, which prevents air pressure from equalizing normally. People with these problems may experience significant discomfort. They may benefit from taking decongestants before flying or by blowing hard against a closed mouth and pinched nostrils to equalize air pressure.
Children are particularly susceptible to the pain of unequal air pressure. They should chew gum, suck hard candy, or be given something to drink during ascent and descent to encourage swallowing. Babies can be breastfed or given a bottle or pacifier.
Sleep Disturbance
Sleep disturbance after air travel (jet lag) is common when people travel across more than 3 time zones. Sleep disturbance does not occur with sea, rail, or car travel because travelers have time to adjust to time zone changes. The most obvious symptom is fatigue on arrival. Other symptoms include irritability, difficulty sleeping (insomnia), headache, and difficulty concentrating. Jet lag can be minimized by starting to adjust sleep and wake times 1 or 2 days before departure to coincide with those of the destination time zone. In flight, a person should drink plenty of fluids and avoid smoking, caffeine, and excessive alcohol. Managing exposure to light can also help travelers adjust to a new time zone.
Westward Travel: People traveling westward tend to awaken earlier and feel tired earlier than they should by local time. For example, if people who normally wake up at 7 AM and go to bed at 11 PM travel 3 time zones west, they tend to awaken at 4 AM local time and feel the need for sleep by 8 PM. To adjust, people should try to get bright sunlight in the late afternoon and try to stay up until the appropriate bedtime.
Eastward Travel: People traveling eastward tend to awaken later and stay awake longer than they should by local time. For example, if people who normally wake up at 7 AM and go to bed at 11 PM travel 3 time zones east, they tend to awaken at 10 AM local time and not feel the need for sleep until 2 AM. To adjust, people should get bright sunlight in the early morning. Those who had an overnight flight should try to remain physically active until evening and try not to nap.
Short-acting sedatives may help people fall asleep at the appropriate local time after eastward travel. However, sedatives may have side effects, such as daytime drowsiness, amnesia, and nighttime insomnia. Long-acting sedatives, such as diazepam, can cause confusion and falls in older people and should be avoided.
The hormone melatonin regulates the sleep-wake cycle. Some doctors have recommended using melatonin supplements after eastward travel to reset the body’s internal clock for sleep. Although some travelers report melatonin is beneficial, its effectiveness and safety have not been thoroughly proved.
Dehydration
Dehydration while flying is common because of the low humidity in airplanes. Dehydration tends to affect older people and people who have certain medical conditions, such as diabetes or who take drugs used to increase sodium and water excretion in the urine (diuretics). The main symptoms are light-headedness, drowsiness, confusion, and, occasionally, fainting.
Dehydration can be prevented by drinking fluids and by avoiding alcohol and caffeine. Dry skin can be treated with moisturizers.
Spread of Infection
Spread of infection on airplanes and cruise ships often receives media attention but is relatively uncommon. Concern is greatest for influenza, viral diarrhea, and bacterial meningitis. Travelers can minimize their risk of influenza by making sure they have received the most current influenza vaccine. They can minimize their risk of diarrhea by washing their hands frequently. There is no reliable way to prevent bacterial meningitis. Some cruise ships offer antibiotics to passengers who have been in close contact with passengers who have these infections.
Minor Injuries
Minor injuries are common. Unaccustomed lifting of heavy luggage is a common cause of shoulder injuries. Luggage falling out of overhead storage bins can cause other significant injuries. During ship travel, injuries can be prevented by wearing shoes that provide good traction on wet surfaces, using handrails and removing sunglasses before entering ship stairwells, and remaining alert in unfamiliar surroundings. A flashlight is useful for preventing falls at night.
Anxiety
Anxiety affects many people who travel. Fear of flying, fear of confined spaces, and worries about medical conditions worsening during flight are common sources of anxiety. Anxiety can cause insomnia, making jet lag worse. People may hyperventilate, often with symptoms such as chest pain, trouble breathing, muscle spasms, and tingling in the arms and hands and around the mouth. The company of a seasoned traveler or caregiver may help relieve anxiety. Cognitive therapy and desensitization programs or hypnosis may also help. Sedatives or antianxiety drugs, such as zolpidem or alprazolam, may be of benefit (see table on page 855).
Specific Medical Conditions and Travel
People with certain medical conditions encounter special problems in transit.
Heart Disease
If people with angina pectoris, heart failure, or rhythm disturbances have symptoms during rest or with minimal exertion, they should not travel. If people have had a heart attack within the past 4 weeks or a heart attack causing shock or heart failure within the past 6 weeks, they are advised not to travel. People with severe or worsening angina should avoid flying. Their symptoms may worsen because less oxygen is available at high altitudes.
All travelers with heart disease should carry a copy of a recent electrocardiogram. People with pacemakers, implantable defibrillators, or coronary stents should carry a card or doctor’s letter documenting the presence, type, location, and electronic characteristics of the implanted device. An implanted metal device may trigger an alarm as the person passes through electronic security. Electronic security devices do not generally affect implantable defibrillators, but travelers are advised to avoid standing in walk-through metal detectors for more than 15 seconds. Hand-held metal detectors are also safe for people with defibrillators, but prolonged contact, such as holding the detector over the defibrillator for more than 5 seconds, should be avoided.
If given 24 hours’ notice, most major airlines can provide low-sodium, low-fat meals on flights with regular meal service. If notified in advance, many cruise lines can also provide these meals.
Did You Know…
At high altitudes, symptoms of certain heart and lung disorders and sickle cell anemia can worsen because less oxygen is available.
Lung Disease
Travelers with lung cysts, severe emphysema, a large collection of fluid around the lungs (pleural effusion), or recent lung collapse or who have had recent chest surgery can develop complications caused by airplane pressure changes. They should not fly without approval from their doctor.
Other travelers with lung disease may need supplemental oxygen while they are aboard an airplane. A doctor determines a person’s need for in-flight oxygen by measuring the level of oxygen in the blood. Airlines will provide in-flight oxygen if they are given a doctor’s prescription and 48 hours’ notice. Travelers are not allowed to carry oxygen in any form aboard an airplane. Travelers who need oxygen during airport layovers must make their own arrangements, although most oxygen vendors will assist their regular customers without charge if they have services in the destination city. Other respiratory equipment, such as continuous positive airway pressure devices, can be accommodated on an airplane provided the equipment does not exceed the size allowed for carry-on luggage. However, travelers who need this equipment should allow extra time for security checks.
Ground travel at high altitudes may present special problems because less oxygen is available than at sea level. In general, people with mild or moderate lung problems do not experience any difficulty at altitudes below 5000 feet, but the higher the altitude, the greater the chance of problems. People with lung disease traveling in or through such areas should take the same precautions that they would if they were flying.
Bus, train, car, and ship travel is safe for people with lung disease but requires planning to ensure a supply of oxygen. Commercial services can coordinate oxygen deliveries for travelers anywhere in the world.
People with asthma, emphysema, or bronchitis may find that their symptoms worsen in cities where air pollution is significant. They may need additional treatment with their inhalers or additional drugs, such as corticosteroids, to control symptoms adequately.
Diabetes
Blood sugar levels are best managed in transit by frequent testing, with adjustments of food intake and drug doses as needed. Travelers with diabetes should pack sugar (glucose) supplements in their carry-on bags or carry juice, crackers, and fruit for when blood sugar levels are low. If travel plans incur time changes of more than a few hours, people with diabetes, especially those taking insulin, should consult with a doctor about how best to schedule their drugs. Insulin can be stored without refrigeration for many days but should be kept out of extreme heat.
If given 24 hours’ notice, most major airlines provide special meals for people with diabetes. Measures to prevent dehydration while in flight are important.
Did You Know…
When people with diabetes are traveling, target blood sugar levels should be slightly higher than when not traveling.
Blood sugar levels should be monitored frequently on arrival because activities and diet often differ from those at home. Because controlling blood sugar levels precisely is more difficult while traveling, levels tend to vary more than usual. Trying to keep levels very close to normal thus increases the risk that levels may sometimes become too low. For this reason, target blood sugar levels should be somewhat higher than ideal while traveling. Diabetic travelers should adhere to established diets despite temptations to try new foods and to eat more frequently or off schedule. They should wear comfortable socks and shoes, check their feet daily, and avoid walking barefoot to prevent minor injuries that may become infected or be slow to heal.
Pregnancy
Pregnancy is generally not affected by travel. However, pregnant women who are close to their due date (over 36 weeks) and those at risk of miscarriage, premature delivery, or placental abruption should avoid flying and traveling long distances. Most airlines have policies regarding travel for pregnant women, and these policies should be checked before tickets are purchased. Pregnant women traveling long distances should take precautions to reduce the risk of blood clots (such as getting up often when traveling by airplane and stopping to take short walks when traveling by car) and dehydration. Seat belts should be fastened below the abdomen and across the hips to prevent injury to the fetus.
Vaccines containing a virus that has been weakened but not killed—for example, yellow fever and measles-mumps-rubella—are not safe for pregnant women.
Pregnant women should avoid prolonged use of water purification tablets that contain iodine because iodine can affect development of the thyroid gland in the fetus.
Pregnant women who cannot postpone travel to regions of the world where malaria is common must weigh the risks of taking protective drugs whose effects on pregnancy are not well known against those of traveling without adequate protection. Malarial infection is more likely to be serious and life threatening among pregnant women than among women who are not pregnant, even when preventive drugs are used.
Pregnant women are also at risk of contracting hepatitis E infection, a viral liver infection rare in the United States but common in Asia, the Middle East, North Africa, and Mexico (see table on page 229). Miscarriage, liver failure, or death may result. There is no treatment, so postponing travel to regions where hepatitis E is common should be considered. Women who cannot postpone travel should be vigilant about hand washing.
Other Conditions
Travel and transit also affect other medical conditions.
Some travelers with sickle cell disease are at risk of experiencing pain (sickle cell crisis) when exposed to the low humidity and low oxygen levels in airplane cabins. This risk can be minimized with adequate hydration and oxygen.
Drugs used to treat human immunodeficiency virus (HIV) infection or AIDS may interact with drugs frequently taken by international travelers to prevent malaria and traveler’s diarrhea. So affected travelers should discuss the risk of such interactions with their doctors and pharmacist.
People with a colostomy should wear a large bag or bring extra supplies because fecal output may increase with expansion of intestinal gas during flight. Because gas expands in flight, water should be substituted for air in devices secured by air-filled cuffs or balloons, such as feeding tubes and urinary catheters.
People who wear contact lenses may want to wear eyeglasses en route or wet their lenses frequently with artificial tears to compensate for low humidity in the airplane. Artificial tears may be helpful for people with dry eyes. In general, bringing an extra set of eyeglasses or lenses or a prescription in case replacements are necessary is a good idea. Extra batteries for hearing aids may also be useful.
Travelers with serious mental health disorders, such as poorly controlled schizophrenia, may pose a risk to themselves or others and should be accompanied by a responsible attendant. Sedating drugs may be recommended also.
Most airlines provide disabled travelers with wheelchairs and stretchers on commercial flights. Some airlines accommodate travelers who need special equipment, such as intravenous lines or ventilators, as long as trained personnel accompany them and arrangements have been made in advance.
General advice about traveling with various medical conditions can be obtained from the medical departments of major airlines, from the Federal Aviation Administration (www.faa.gov), from online travel information sources (see page 2164), or from local travel clinics.
Problems at the Destination
Problems after arrival are especially important to prevent and avoid in international settings. Though many people are most concerned about infection when considering a trip overseas, heart disease is the most common cause of death among international travelers. Heart disease is the most common cause of death among nontravelers as well, suggesting that attention to health before leaving home is the best way to prevent illness while away.
Injuries
Injuries are the most common cause of death among younger and middle-aged travelers. The most common are due to motor vehicle or water accidents. Commonsense measures can be taken to prevent many such injuries. For example, people uncomfortable with unfamiliar traffic patterns (such as driving on the left side of the road in England versus the right side in the United States) can take public transportation or hire drivers familiar with local roads and traffic laws. Travelers should avoid overcrowded taxis, ferries, or other transports and avoid nighttime driving and swimming in poorly lit areas. People should wear seat belts even as passengers and should use a helmet when cycling. Travelers should avoid motorcycles and mopeds and avoid riding on bus roofs or in open truck beds. Also, alcohol should never be consumed before driving or swimming, even where laws do not formally prohibit such actions or where laws that do exist are not enforced.
Many cities are unsafe after dark, and some are unsafe even during the day. A traveler should avoid walking alone on ill-lit or deserted streets in such cities, especially in countries where the traveler is obviously a stranger.
Did You Know…
The most common cause of death among younger and middle-aged travelers is injury.
Traveler’s Diarrhea
Traveler’s diarrhea (see page 152) is the most common infectious disease among international travelers.
The risk of traveler’s diarrhea may be reduced by the following measures:
Drinking and brushing teeth with bottled, filtered, boiled, or chlorinated water
Avoiding ice
Eating freshly prepared foods only if they have been heated to steaming temperatures
Eating only fruits and vegetables that people peel or shell themselves
Avoiding food from street vendors
Washing hands frequently
Avoiding all foods likely to have been exposed to flies
Taking certain antibiotics can also prevent traveler’s diarrhea. However, such use has a risk of side effects and may increase the chances that bacteria will develop resistance to antibiotics. Thus, many doctors recommend preventive antibiotics only for people who have an immune deficiency disorder.
In most cases, traveler’s diarrhea subsides by itself and requires only the steady intake of fluids to prevent dehydration. Ordinary clear liquids (without caffeine or alcohol) are adequate for most people. Young children and older people may benefit from powdered rehydration mixes or an oral rehydration solution. Other measures, though not always necessary, may be helpful.
People who have moderate to severe symptoms (3 or more unformed stools over 8 hours) should consider taking an antibiotic, especially if they have vomiting, fever, abdominal cramps, or blood in the stool. For most destinations, the appropriate antibiotic is ciprofloxacin or ofloxacin. Azithromycin is appropriate for Southeast Asia and the Indian subcontinent. People should contact their doctor for an antibiotic prescription before travel. If people are older than 6 years of age and have no bloody stools, fever, or abdominal pain, they can also be treated with the antidiarrheal drug loperamide (which is available without a prescription).
For older adults and young children, powdered rehydration mixes are available for travel. If these mixes are unavailable, rehydration solutions can be made with small amounts of salt, baking soda, and sugar or honey mixed in water. However, solutions should be prepared carefully because young children can become seriously ill or die if they drink much of a solution that has been incorrectly mixed (for example, if a rehydration mix has not been fully diluted).
Malaria
Malaria (see page 1218) is common throughout the tropics. Malaria is prevented by avoiding mosquito bites and taking an antimalarial drug. Mosquito bites are prevented by the following measures:
Wearing long-sleeved shirts and long trousers (especially at dawn and dusk, when mosquitoes are most active)
Sleeping under a mosquito net
Wearing clothing impregnated with permethrin
Using insect repellants that contain diethyltoluamide (DEET)
Insect repellants can also help prevent other mosquito-borne diseases such as dengue and yellow fever. Even with these measures, taking an antimalarial drug (such as mefloquine, chloroquine, or atovaquone/ proguanil) is necessary.
Schistosomiasis
Schistosomiasis is a common and potentially serious infection caused by a parasite that lives in fresh water in Africa, Southeast Asia, China, and eastern South America. Schistosomiasis can be prevented by avoiding freshwater activities in areas in which schistosomiasis is common (see page 1222).
Lice and Scabies
Lice and scabies are common in crowded accomodations, underdeveloped areas, and places where hygiene measures are poor (see page 1312). Infestations can be treated with permethrin, malathion, or lindane lotions. However, these lotions should not be used to prevent infestations.
Sexually Transmitted Infections
Sexually transmitted infections, including human immunodeficiency virus (HIV) infection, gonorrhea, syphilis, trichomoniasis, and hepatitis B, are more common in developing countries. All can be prevented through abstinence or with correct, consistent use of a condom (see box on page 1265). Because HIV and hepatitis B also are transmitted through blood and needles, an international traveler should not accept a blood transfusion without assurance that the blood has been tested for infection. Also, injections should be accepted only through one-time-only disposable needles.
Problems After Travel
Symptoms or problems that develop during travel and that do not subside by the time a person returns home warrant medical attention.
Travel-related problems can also develop after travel. For example, nitrogen narcosis (the bends) can occur after a diver gets on the plane to go home (see page 1998). Some symptoms may develop weeks or months after a person has returned. Fever after international travel is especially common. For example, malaria often causes fever days after exposure. Although the connection between travel and new symptoms often is not apparent, information about recent travel can be the key element in making a diagnosis. Therefore, people should tell their doctor about any recent travel when they experience any medical problem.
Both the International Society of Travel Medicine (www.istm.org) and the American Society of Tropical Medicine and Hygiene (www.astmh.org) have lists of travel clinics on their web sites. Many of these clinics specialize in assisting travelers who are ill after they return home.