More than 50 million people travel to the tropics and the developing world every year and are exposed to diseases that are not commonly seen in the United States and other developed countries. Even though child travelers represent only a small fraction of this number, they constitute about a quarter of all travel-related hospital admissions.1 Management of sick children after international travel is complicated: febrile illness caused by common, universally transmitted infections such as respiratory and gastrointestinal viruses is extremely common in this population, yet children are also vulnerable to tropical infections acquired during the travel. Although pediatric data are lacking, the etiology of fever among returned travelers is generally equally distributed among the tropical diseases, commonly acquired infections (those found both in developed and developing countries) and illnesses of unknown etiology. Thus, a complete evaluation requires elements that are not usually included in a general pediatric review: assessment of travel vaccinations and prophylaxis, specific destination and exposure history, and probable incubation period. The most common tropical diseases in the returning traveler are malaria, traveler's diarrhea, dengue, rickettsiosis, and typhoid fever.
Resources available to assist in this evaluation include the Centers for Disease Control (CDC) travel Web site (http://www.cdc.gov/travel), the CDC's publication entitled Health Information for International Travel also known as The Yellow Book (http://www.cdc.gov/travel/yb/) and the World Health Organization Web site with information on the health risks by country (http://www.who.int/countries/en/). Physician-staffed travel medicine clinics are also a good source of support when evaluating illness in returned travelers.
Evaluation of Fever after Travel
Immunization records, and especially-travel specific immunization records that are often recorded on an International Certificate of Vaccination, may help to guide the evaluation. Some immunizations are highly effective and patients who have been vaccinated are at almost no risk for disease. These infections include hepatitis A and yellow fever. Other vaccines provide incomplete protection. The typhoid fever vaccinations (live and inactivated) have 50–80% efficacy against Salmonella typhi and offer no or limited protection against Salmonella paratyphi, an increasingly common cause of typhoid fever. The polysaccharide and conjugate Neisseria meningitidis vaccines only prevent infection with serotypes A, C, Y, and W-135.
For patients who attended a travel clinic prior to travel, antimalarial medication may have been prescribed. Compliance with antimalarial prophylaxis is often poor because of the requirement for prolonged administration and real or perceived side effects. In the United States, approximately 20% of cases of malaria among travelers occured in individuals who reported taking appropriate prophylaxis.2
Self-treatment for traveler's diarrhea while abroad is generally recommended. For returned travelers, it is possible that febrile illnesses were partially treated by short courses of therapy with azithromycin, fluoroquinolones, or antifolates. These medications may alter the typical presentation or interfere with diagnosis of bacterial and parasitic infections, including typhoid fever ...