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Almost 500 million people annually venturing across international borders. Of these, it is estimated that 40 million Americans travel or work abroad annually. Although most travelers complete their business or holiday without medical upset, many have special medical needs that require individualized attention before their departure or develop problems while abroad.
Family physicians are in an excellent position to provide valuable pretravel counseling for patients and attend to the needs of returning travelers. Although many physicians associate travel medicine with rare and exotic tropical illnesses, most morbidity that occurs during
The most critical encounter with a prospective traveler is the pretravel brief. During this session, it is essential to review the traveler's proposed itinerary, medical history, current medications and current immunization status. In many offices, patients are asked to complete a short questionnaire before the visit to help the staff efficiently target issues that need to be addressed (Appendix A).
The pretravel brief should focus on the following issues:
1. Immunization review and update.
2. Behavioral counseling (food and water precautions, protective measures against insect bites, safe sexual behavior, motor vehicle safety, etc.).
3. Prevention of malaria and other insect-borne diseases.
4. Management of traveler's diarrhea (recognition of symptoms, initiation of self-treatment).
5. Prevention of sexually transmitted diseases.
Immunizations
Immunizations are the cornerstone of preventive medicine for travelers. In general, there are three classes of immunizations to consider for travelers: routine immunizations.
Routine Immunizations
Diphtheria, Tetanus, Pertussis and Haemophilus influenzae Type B. All adult travelers should be advised to have current (within 10 years) immunization against diphtheria and tetanus. Travelers to the former Soviet Union should be aware of recent diphtheria epidemics. For travelers requiring booster doses, the combination vaccine with tetanus and diphtheria toxoid (Td) should be used.
Measles, Mumps and Rubella. Measles (rubeola) remains endemic in many developing nations. For this reason, all travelers to developing countries should have current vaccination
Varicella. Vaccination against varicella zoster is now routinely offered as a part of the primary childhood immunization schedule. There are no special considerations for travelers.
Hepatitis B, Since the introduction of the recombinant DNA vaccine against hepatitis B, universal immunization during infancy has been widely endorsed, and hepatitis B vaccine is now considered.
CONDITIONAL ROUTINE IMMUNIZATIONS
Pneumococcal Pneumonia. Vaccination with the polyvalent pneumococcal preparation should be considered in all persons over age 65, asplenic persons and those with specific comorbid conditions, such as diabetes mellitus or chronic lung disease. Travel confers no added risk.
TRAVEL-SPECIFIC IMMUNIZATIONS
Hepatitis A. Hepatitis A is the most common vaccine-preventable illness acquired by travelers. It is critical that at-risk individuals receive vaccination against hepatitis A. Before 1995, individuals at risk were given prophylactic immune globulin. Travelers from the United States to areas outside of Canada, Japan, Australia, Scandinavia or Western Europe (Figure 1) should now receive the hepatitis A vaccine rather than immune globulin. Hepatitis A vaccine (Havrix®, Vaqta®) is
Yellow Fever. Yellow fever vaccine (YF-Vax) is the only remaining vaccination required for entry 1o some countries. It is a live virus preparation made from the 171) strain of the yellow fever virus. The World Health
Cholera. No countries officially require proof of immunization against cholera before entry. The parenteral vaccine is a killed bacterial preparation that confers incomplete immunity. Several promising oral vaccines against
Typhoid. Three preparations are available for immunization against typhoid fever. This vaccination should be
Plague. Plague vaccine is a killed bacterial preparation and is not recommended for the routine traveler. Candidates for the vaccine include persons with prolonged occupational exposures, such as anthropologists or
Typhus. Typhus vaccination is not recommended, and manufacturing of the vaccine has been discontinued in the United States.
Meningococcal Meningitis. Meningococcal vaccine (Menomune®) is indicated for pilgrims to Saudi Arabia during the Hajj season. Other potential recipients include travelers to epidemic areas, such as sub-Saharan Africa,
Rabies. Rabies-infected animals can be found around the globe. Preexposure prophylaxis with human diploid cell rabies vaccine (Imovax®) should be considered only in travelers at particularly high risk of acquiring a wild
Japanese Encephalitis. Japanese encephalitis vaccine 0E-VAX®) is a killed viral preparation and is recommended for travelers who anticipate a prolonged stay in endemic areas, such as rural Asia, where they
Tuberculosis. The bacille Calmette-Guerin (BCG) vaccine is not routinely recommended in areas with ongoing
Protective Measures Against Insect Bites
Another critical function of the pretravel brief is to provide the traveler with a thorough review of protective measures to prevent insect bites (Table 3). Although vaccinations are available against several of the more
ALTITUDE SICKNESS
Altitude sickness refers to a continuum of pathophysiologic processes that occur when a person is exposed to continuous ambient altitudes that are higher than normal for the individual. In areas of higher elevation, less
JET LAG
Jet lag refers to the physiologic and psychologic changes that occur when travelers rapidly cross multiple time zones. Symptoms are primarily due to an alteration of innate circadian cycles. Social and environmental cues
Food- and Waterborne Illnesses
After leaving the Caribbean Islands, the Joneses plan to travel to South America, heading to Brazil for Carnival. They will also visit Uruguay, Argentina and the Falkland Island&
Various diseases are transmitted through contaminated food or water. Travelers must comply with safe food and beverage precautions to minimize the risk of acquiring such diseases.
TRAVELER'S DIARRHEA
Traveler's diarrhea is the most frequently encountered pathogenic state associated with international travel. Between 20 and 40 percent of short-term travelers mad 70 percent of long-term travelers experience one or more episodes of diarrheal illness while abroad, representing approximately 300 million cases of traveler's diarrhea per year. Studies have shown that despite adequate counseling and knowledge regarding proper food and water
Causes of traveler's diarrhea are listed in Table 9. Enterotoxigenic strains of Escherich-ia colt account for 33 percent of all cases, so Illness is due to the production of an entero-toxin that creates a secretory state within the bowel lumen. Salmonella, Shigella and Campylobacter species are other bacterial causes of traveler's diarrhea. Vibrio para-haemoIticus has also been associated with acute diarrheal illness, and infection usually results from consuming raw or inadequately cooked seafood. Viral causes are presumed to be common. Parasitic (e.g., Giardia) and protozoal (e.g., Cryptosporidium) infections are unusual causes (Table 9).
HEPATITIS A
As previously mentioned, hepatitis A is the most frequent vaccine-preventable infection in travelers. It is primarily acquired via the fecal-oral route and usually results from contaminated food, water or ice.