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When families seek advice before they travel, pediatricians need to know where to find information about required vaccinations and to be aware of the potential risks and hazards there.
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When families seek advice before they travel, pediatricians need to know where to find information about required vaccinations for the destination country and to be aware of the potential risks and hazards there.
Many pediatricians care for children who vacation with their families overseas or need assistance in preparing to emigrate. These families may well ask your advice about how they should prepare for these trips and how to guard their children's health while out of the country. To provide good counsel, you need to be aware of the many considerations overseas travel presents and be able to refer families to sources of information about specific needs in the area to which they are traveling.
More than 30 million Americans travel overseas every year. Roughly a quarter of these trips are to lesser developed countries in Africa, Asia, and Latin America. A person who stays a month or longer in these countries has a more than 60% chance of contracting an illness during the trip.1 Travelers can minimize their chance of getting ill by familiarizing themselves with the infectious diseases common in the countries on their itinerary so they can take appropriate precautions. Travel preparations for children include making sure that routine immunizations are current and administering age-appropriate travel vaccines prior to departure. Because health-care services vary tremendously throughout the world, parents should be advised to prepare or purchase a travel medical kit (contents are discussed later in this article) and may need to have supplies for sanitizing water, repelling insects, and treating traveler's diarrhea.
Unless you are prepared to expand your practice to include travel medicine, it is a good idea to refer parents to a local clinic or medical office that specializes in travel medicine and to expect to comply fully with their recommendations. In addition to hundreds of travel clinics located around the country, Web-based services ( such as www.thetraveldoctor.com ) offer online travel consultations for $25. Compared with these online services, travel clinics offer the advantages of face-to-face consultations between physicians and families to discuss trip preparation for the particular areas of the world being visited and routinely stock and administer travel vaccines. An extensive list of United States clinics can be found at www.travmed.com . In addition, the public health department in every state maintains a list of approved travel medicine clinics.
Other sources of information about travelers' health needs are readily available. The Centers for Disease Control and Prevention (CDC) has a toll-free voice and fax service for travelers, a malaria hotline for physicians, and a Web site with current information about risks of diseases around the world. The CDC travelers' health Web site ( www.cdc.gov/travel ) has a quick-search feature that makes it easy to learn what diseases are endemic in countries being visited, as well as the vaccines required and recommended for travel to those areas. The site also has a free downloadable version of "Health Information for International Travel," known as the Yellow Book. It contains detailed listings and discussions of all travel vaccine recommendations; bacterial, viral, and parasitic diseases in various regions and countries; and applicable vaccine recommendations and precautions. The Yellow Book is updated every two years. In addition, the CDC site publishes an online version of the so-called Blue Sheet, which provides a comprehensive listing of countries reporting active cases of cholera, yellow fever, or plague, or changes in routine country-specific recommendations, based on current disease outbreak information. This information is updated as necessary. Table 1 lists resources for health-related travel information and services.
Concern about exotic infectious diseases may keep parents and pediatricians from focusing on health concerns that are just as important when traveling abroad as they are at home.
Motor vehicle accidents and drowning are far greater threats when traveling than contracting an infectious disease. Death rates because of motor vehicle accidents in some countries are 20% to 80% higher than they are in the United States.1,2 This underscores why you should remind parents to make arrangements for car seats when traveling. You should also repeat cautions and advice about water safety.
Chronic illness. Be sure to give prescriptions for medications or equipment that may be needed to parents of a child with a chronic illness. Such equipment may include glucose test strips, glucose analyzer, nebulizer, and syringes. It is a good idea to provide letters that document the child's medications, allergies, medical history, and medical needs.
Environmental hazards. Hotel rooms need to be inspected for electrical hazards, access to poisons, unguarded stairs, unsecured windows, and other such hazards. Because of potential exposure to parasites, children should be discouraged from walking barefoot, and they should wear an effective insect repellent to prevent malaria. Generally, insect repellents containing up to 30% Deet are considered safe and effective. Additional protection is provided by saturating clothes with a permethrin preparation, which bonds to fabric; one application lasts a minimum of two weeks. If the child is travelling to a tropical area, a sunscreen preparation with a sun protection factor of 15 or higher is a necessity. Proper food preparation and hygiene are also important.
Two or three months before departure, parents should check their insurance coverage, bring routine childhood immunizations up to date (or accelerate them depending on circumstances), and assemble a medicine kit.
Health insurance. Encourage parents to ask their insurers whether their insurance plan provides coverage overseas. Depending on their travel plans, parents can obtain lists of doctors from organizations such as the International Association for Assistance to Travelers or Personal Physicians Worldwide. The American embassy or consulates in the country being visited are excellent resources for getting the names of competent health-care providers. Many insurance plans do cover medical care overseas, but patients may be required to pay up front and submit receipts for reimbursement. Furthermore, as we all know, many health maintenance organizations need to preauthorize admission to a hospital (which can be difficult to do overseas), and will not cover "nonemergency" medical visits. Parents have the option of purchasing additional travel health insurance at reasonable rates. Such coverage provides access to a multilingual medical assistance center and emergency air ambulance transport and guarantees payments to physicians, to avoid unexpected out-of-pocket expenses.
Routine childhood immunizations. American children have benefited from an aggressive immunization schedule that provides ongoing protection against many childhood illnesses. Many infectious diseases that are now encountered only infrequently in the United States remain endemic in many developing countries. It is very important, therefore, to ensure that the child who is leaving the country is brought up to date with any lapsed immunizations.3
Diphtheria is still endemic in many areas of the world and tetanus and pertussis are also common. Children who are younger than 1 year of age are considered optimally protected after three doses of DTaP vaccine. As pediatricians know, DTaP can be given as early as 6 weeks of age, and the minimal interval between vaccinations is four weeks. For additional protection, the fourth dose can be given a minimum of six months after the third dose.
Measles is much more common in developing countries than it is in the United States, so adequate protection is important. Measles is typically part of the measles, mumps, rubella (MMR) vaccine after 12 months of age, with a booster dose at school entry. If travel is to an area where measles incidence is high, infants between 6 and 12 months of age may receive a dose of measles or MMR vaccine, though they still need the standard two-dose regimen after their first birthday.
Similarly, polio continues to be endemic in some areas. Inactivated polio vaccine (IPV) can be given as early as 6 weeks of age with second and third doses given as early as four weeks after the preceding dose. While the fourth dose of IPV is typically given when the child is between 4 and 6 years of age, for optimal protection it may be given as early as 4 weeks following the third dose.
Children who have never received Haemophilus influenzae type b (Hib) vaccine should have two doses separated by four weeks if they are younger than 15 months, while children older than 15 months should receive a single dose.
Children who will reside for several months in an area where hepatitis B is common would benefit by completing a full hepatitis B series before departure. The full series consists of three vaccinations, with the second dose administered one to two months after the first. While the third dose is typically given four to 12 months after the second vaccination, this interval can be reduced to no less than two months.
Table 2 summarizes minimum age and accelerated dosing intervals for routine childhood immunizations.
|Vaccine||Routine administration||Accelerated schedule|
|DTaP||2, 4, 6, and 1518 mo, age 46 yr. Tetanus every 10 yr||6, 10, and 14 wk of age; 4th dose six mo after 3rd|
|MMR||First dose at 1215 mo, second at 46 yr||Extra dose at 6 mo, 2nd one mo after 1st if 1st after 12 mo of age|
|Polio (IPV)||2, 4, and 1218 mo, 46 yr||6, 10, and 14 wk of age; 4th dose four wk after 3rd|
|Hib||2, 4, and 6 mo, 1 dose after 1||6, 10, and 14 wk of age|
Medicine kit. Assembled by parents, this important travel accessory should include an abundant supply of routine medications, in addition to analgesics, antihistamines, steroid creams, antifungal creams, oral rehydration solutions, antimalaria prophylaxis medications, or prescribed antibiotics for treatment of traveler's diarrhea, when appropriate (Table 3). Kits should also include a good insect repellent. A variety of travel products, including a well-stocked travel medicine kit, permethrin clothing spray, mosquito netting and a rapid malaria test kit, tick removal kit, and water purification systems, can be ordered by mail or on the Web from companies such as Travel Medicine ( 369 Pleasant Street, Northampton, MA 01060, 800-872-8633, or www.travmed.com ). If medical equipment (such as a nebulizer) is to be taken overseas, it is important to pack adapters for use with foreign electric current.
|Medications||Topical steroids and antifungals Trimethroprim and sulfamethoxazole (Septra) or ciprofloxacin hydrochloride (Cipro) for travelers diarrhea in children older than 12 years Water purification supplies|
Flight preparations. Parents should prepare their child for the trip by reviewing and explaining the itinerary well in advance of the departure date. Since young children have short attention spans, it's a good idea to pack books, small electronic games, stickers, and snacks to make the trip pleasant for everyone. Dimenhydrinate (Dramamine), given in a dose of 1 to 1.5 mg every six hours and started about one hour before the flight, should be considered for the child with a history of motion sickness. In addition, diphenhydramine (Benadryl) in a dose of 1 mg/kg every six hours can be used as a sedative; however, parents should test the medication on the child before departing to ensure that it doesn't produce paradoxical excitement. To avoid ear discomfort associated with altitude changes during flight, infants should be offered a pacifier or bottle as needed. Older children can be taught to yawn or chew gum.4
Many travelers and their families risk exposure to a variety of illnesses not covered by standard immunizations, including malaria, typhoid fever, yellow fever, cholera, hepatitis A, Japanese encephalitis, and, sometimes, meningococcal disease and rabies. Numerous countries require an International Certificate of Vaccination against yellow fever before a traveler is permitted entrance. Only registered travel clinics are authorized to stock and administer yellow fever vaccine and provide travelers with this certificate.
Hepatitis A. In some underdeveloped countries, families and children may live in areas where sanitation is questionable. In the child younger than 2 years, hepatitis A may be prevented with immune globulin given before departure and, in the older child, with hepatitis A vaccine. As of this writing, immune globulin has been in short supply and may be extremely difficult to obtain. The dose of immune globulin varies with the weight of the child and the anticipated length of stay overseas (Table 4). Keep in mind that immune globulin can reduce the antibody response to MMR and varicella vaccines. Typically, vaccination with either of these vaccines should be delayed up to 11 months following administration of immune globulin.
|Length of travel||Body weight||Dose volume|
|Short term (||2345 kg >45 kg||0.5 mL 1 mL 2 mL|
|Long-term (35 mos)||2345 kg >45 kg||0.5 mL 1 mL 2.5 mL 5 mL|
Two hepatitis A vaccines are available for use in children older than 2 years. Havrix is given as two pediatric doses (720 EL.U.) separated by six to 12 months. VAQTA is given to children in two 25 U doses six to 18 months apart.
Typhoid fever is common in many areas of Asia, Africa, and South America. The illness is caused by strains of Salmonella typhi and is associated with vomiting, diarrhea, fever, and chills. The risk to travelers may be as high as one in 3,000 travelers a month in areas of India, Peru, Pakistan, and Bangladesh. The three typhoid vaccines available in the United States have been shown to protect up to 80% of vaccine recipients. Oral live attenuated Ty21 is a capsule swallowed with cool water one hour before a meal on alternate days for a total of four doses. Because of compliance issues, oral typhoid vaccine is not routinely recommended for children younger than 6 years. A booster dose of one capsule is given every five years. An alternative to the oral vaccine is a single dose of Typhim Vi (a polysaccharide vaccine). It can be administered intramuscularly to children older than 2 years with a booster dose every two years. For younger children, a heat-inactivated parenteral vaccine can be given to infants older than 6 months in a two-dose regimen given four weeks apart. Boosters can be given every three years.
Cholera is an intestinal infection caused by two serotypes of toxigenic Vibrio cholerae. Treatment usually requires oral rehydration plus doxycycline for children older than 8 years or erythromycin for young children. Cholera vaccine is considered highly ineffective, protecting fewer than 50% of vaccinated individuals and often for less than six months. The vaccine is not required for travel to any territory or country. Usually, adequate food preparation and handling can prevent transmission of cholera. If requested, cholera vaccine is given in two doses one to four weeks apart but is not recommended for infants younger than 6 months.
Yellow fever, caused by a mosquito- transmitted arbovirus, is seen only in South America and Africa. Clinical illness ranges from mild constitutional symptoms to multiorgan infection with renal and liver failure. Jaundice is seen in 15% of cases. Prevention is accomplished with a single subcutaneous dose of yellow fever vaccine, which can be given to infants as young as 9 months. The vaccine is close to 100% effective and immunity may last a lifetime. A booster dose is given every 10 years. Proof of yellow fever vaccination is required for entry into many countries. According to the CDC, administration of yellow fever and cholera vaccine should be separated by a minimum of three weeks to avoid diminished antibody response to both vaccines.
Rabies. Only a few areas of the world are considered rabies freeAustralia, some countries in Western Europe, several tropical islands, and Hawaii. In many countries, children are likely to have contact with unimmunized cats and dogs and other animals. Parents may therefore wish to consider pre-exposure rabies prophylaxis before taking their children overseas. Three rabies vaccines are available in the United States: a human diploid cell vaccine, a rabies vaccine adsorbed, and purified chick embryo cell culture vaccine. All are available for intramuscular injection, and the human diploid cell vaccine also can be injected intradermally. Adequate prophylaxis is achieved with three doses given on days 0, 7, and 21 to 28. Intramuscular vaccines are given in a volume of 1 mL while the intradermal vaccine is administered in doses of 0.1 mL. The intradermal schedule must be completed two weeks before starting antimalarial medication to avoid reducing vaccine efficacy. This is not an issue with the intramuscular route.
Japanese encephalitis is seen only rarely in Japan but occurs in many other Asian countries, including China and several southern Asian countries. It is an arbovirus infection transmitted by the bite of Culex mosquitoes, in a manner similar to yellow fever. While the overall risk of infection is low, most cases are in children, and symptomatic cases are associated with significant mortality and morbidity. The only Japanese encephalitis vaccine is highly effective: 91% of those vaccinated with a three-dose series demonstrate protective antibody levels. Regrettably, side effects from the vaccine are common and severe. One in 1,000 recipients experiences urticaria or angioedema either immediately or within several weeks of being vaccinated. The vaccine should be considered only if a prolonged stay is anticipated in a rural area where the illness is endemic. The vaccine is administered on a three-dose schedule on days 0, 7, and 30, but can be accelerated to days 0, 7, and 14, with the series to be completed two weeks before departure so that any reactions will have time to manifest and be treated. The vaccine is approved only for children older than 1 year.
Meningococcal disease. Outbreaks of meningococcemia and meningococcal meningitis, typically caused by serotype A meningococcus, is seen frequently in sub-Sahara Africa during the "dry season" from December through June. If visitors anticipate prolonged contact with the local population, vaccination with meningococcal vaccine should be considered. Note that vaccination is required for pilgrims to Saudi Arabia for the annual Hajj. Meningococcal vaccine may be administered to infants older than 2 years.
Table 5 summarizes travel vaccination guidelines.
|Immune globulin||Birth||Intramuscular||Every 6 mo|
|Vaccine||2 yr||Intramuscular||Second dose 612 mo after first dose|
|Parenteral||6 mo||Subcutaneous||2 doses, 4 wk apart|
|Vi capsular||2 yr||Intramuscular||1 dose, booster every 2 yr|
|Ty21a||6 yr||Oral||4 initial doses, booster after 5 yr|
|Yellow fever||9 mo||Subcutaneous||1 dose,1 booster every 10 yr|
|Rabies||1 yr||Intramuscular or intradermal||3 doses, 0, 7, and 2128 d|
|Japanese encephalitis||1 yr||Subcutaneous||3 doses, 0, 7, and 1430 d|
|Meningococcal||2 yr||Subcutaneous||Single dose, booster each 5 yr|
Malaria is caused by several Plasmodium species transmitted by the bite of the Anopheles mosquito. Malaria symptoms can be cyclical, corresponding to the life cycle of the infecting protozoan, and include fever, chills, myalgias, and headache. The World Health Organization publishes monthly updates on the risk of malaria in various countries and monitors the incidence of chloroquine resistance among documented cases. Malaria is common in Central and South America, Africa, India, Southeast Asia, and the Middle East (see figure below). It can be prevented with prophylactic medication, usually chloroquine or mefloquine taken weekly beginning one to two weeks before travel and continued for four weeks after returning to the United States. Occasionally, mefloquine is associated with vomiting, headaches, and fatigue. It is contraindicated in patients with a diagnosis of depression or epilepsy. Doxycycline is an alternative to mefloquine for children older than 8 years (Table 6). A new agent for malaria prophylaxis, Malarone, has recently become available. A combination of atovaquone and proguanil hydrochloride, Malarone is manufactured in adult-strength and pediatric-strength tablets. One adult Malarone tablet contains 250 mg of atovaquone and 100 mg of proguanil; the pediatric tablet has 62.5 mg of atovaquone and 25 mg of proguanil. Malarone is effective for prophylaxis of malaria caused by the chloroquine-resistant Plasmodium species. In contrast to mefloquine, Malarone is administered daily, beginning one to two days before entering an area where malaria is endemic and for seven days on return. The agent is not recommended for children who weigh less than 11 kg.
|Drug||Use||Adult dose||Pediatric dose||Comment|
|Mefloquine (Lariam)||Prophylaxis in areas of chloroquine-resistant malaria||250 mg once a wk beginning 12 wk before travel and for 4 wk after return||1519 kg:||Avoid in patients with epilepsy, psychiatric disorders, or cardiac conduction abnormalities 1 tab = 250 mg|
|Doxycycline||Alternative to mefloquine||100 mg orally/d beginning and ending per the schedule above||>8 years of age: 2 mg/kg po qd||Not for children|
|Chloroquine (Aralen)||Use in areas of chloroquine-sensitive Plasmodium||500 mg once a wk as above||8.3 mg/kg once a wk up to maximum of 500 mg|
|Hydroxychloroquine sulfate (Plaquenil)||Alternative to chloroquine||400 mg once a wk as above||6.5 mg/kg up to max of 400 mg|
|Atovaquone/proguanil (Malarone)||Alternative to mefloquine||1 adult tab/d||1120 kg: 1 ped tab/d 2130-kg: 2 ped tab/d in single dose 3140-kg: 3 ped tab/d in single dose >40 kg: 1 adult tab/d in single dose||For adults and children administer 12 d before travel and for 7 d after return Adult tab = 250 mg atovaquone/100 mg proguanil Ped tab = 62.5 mg atovaquone/25 mg proguanil|
Parents are likely to ask about the best way to avoid water- or foodborne infections, which include a variety of bacterial, viral, and protozoan and helminthic parasites. Advise them to use bottled or purified water for drinking, bathing, tooth brushing, and food preparation. Ice should be avoided as it may contaminate water with pathogens or parasites. Travelers should not eat unpeeled fruits.
Boiling water for one minute and then permitting it to cool is the best method for making water safe for drinking. Treating contaminated water with iodine (tincture or tablets) is an alternative to boiling, but it takes as long as 15 hours to kill Cryptosporidium. Standard chlorine treatment will not kill some viruses and parasites. Several micropore filtration devices are available, the best of which are combined with an on-demand iodine-release system. These devices can effectively remove parasites, bacteria, and viruses. Any device chosen should use a carbon extraction filter to remove residual iodine from the purified water. This will prevent iodine-related thyroid problems caused by long-term consumption of water prepared by purification devices. When safe drinking water is not available, beverages prepared with boiled water, such as tea, are safe, as are canned and bottled beverages. Bottled water from a reliable source outside the country is also considered safe.5
Advise parents to be cautious when choosing food for themselves or their children. All uncooked vegetables, salads, and unpasteurized milk and milk products and poorly prepared meat and fish pose a contamination risk. For infants, breast milk or formula prepared from powder and boiled water is safest.5
Attack rates of traveler's diarrhea can be as high as 20% to 50%; the illness is especially common among travelers to Central America, Africa, the Middle East, and Asia. The incidence of infection is higher among children than among adults. Symptoms typically include several loose, watery stools a day, which may occasionally be bloody or accompanied by fever and vomiting. Typical causative agents include Salmonella species, Shigella, V cholerae, Campylobacter, and enterotoxigenic Escherichia coli. Although prophylactic agents can prevent traveler's diarrhea in more than half of patients taking the medication, their use is not routinely recommended because preserving the efficacy of antimicrobial agents worldwide calls for avoiding unnecessary use of antibiotics.
Adults and children who develop severe traveler's diarrhea should be treated with oral rehydration solution and three days of trimethoprim-sulfamethoxazole (TMP-SMX) or ciprofloxacin for children older than 12 years. Azithromycin is an alternative to TMP-SMX for children younger than 12 years and may, in fact, be preferable in areas where Campylobacter is common, such as Mexico.
Pediatricians can do much to assure that a family's overseas trip is as free from illness and accident as possible. We need to cooperate with the recommendations offered by travel clinics to make sure that children's routine immunizations are current, help the family in preparing or purchasing a travel medicine kit, and remind parents how important it is to remain diligent in safeguarding their children from the many hazards that may threaten them.
The author thanks Joan L. Chase and Virginia A. Mason for assisting in the preparation of the manuscript of this article.
1. Rose SR: 1999 International Travel Health Guide. Northampton, Mass., Travel Medicine Inc 1999, p 1
2. Hostetter MK: Epidemiology of travel-related morbidity and mortality in children. Pediatr Rev 1999;20(7):228
3. Centers for Disease Control and Prevention: Health Information for International Travel 1999-2000. Atlanta, Ga., US Department of Health and Human Services, 2000
4. Fisher PR: Travel with infants and children. Infect Dis Clin North Am 1998;12(2):356
5. Thanassi WR, Weisss EL: Travel-related emergencies: Immunizations and travel. Emerg Med Clin North Am 1997;15(4):43
Andrew Schuman. Preparing children and families to travel overseas. Contemporary Pediatrics 2001;6:45.