Introduction

The number of children who travel or live outside their home countries has increased dramatically. An estimated 1.9 million children travel overseas each year. Health issues related to pediatric international travel are complex, reflecting varied activities, exposures, and age-specific health risks. While some travel health concerns are similar for children and adults, international pediatric travelers have unique problems because of variable immunity and different age-based behavior; for example, a newly mobile toddler will have different health risks than a sexually active adolescent. Furthermore, many travel-related vaccinations and preventive medications used for adults are not licensed or recommended for pediatric use.

Although data about the incidence of pediatric illnesses associated with international travel are limited, studies of pediatric travelers have reported serious morbidity and mortality. The most common reported health problems are diarrheal illnesses, malaria, and motor vehicle- and water-related accidents. Children who are visiting family and relatives living in developing countries are at high risk for a variety of travel-related health problems, including malaria, intestinal parasites, and tuberculosis. In addition, travelers visiting friends and relatives are less likely to seek pre-travel preventive care. Adults and older children should consider taking a course in basic first aid prior to travel.

Clinicians should obtain a complete assessment of travel-related activities and provide preventive counseling and interventions tailored to specific risks. Adults traveling with young children should be counseled to monitor the children carefully for signs of illness. Irritability may be a response to changes in time zone and environment but may also indicate illness in young children. Excessive or persistent irritability, fevers, or signs of dehydration should be evaluated promptly. Children with chronic diseases or immunocompromising conditions require travel preparations and treatment tailored to their specific underlying condition.

Diarrhea and Dehydration

Diarrhea and associated gastrointestinal illness are among the most common travel-related problems affecting children (1). Young children and infants are at high risk for diarrhea and other food- and waterborne illnesses because of limited pre-existing immunity and behavioral factors such as frequent hand-to-mouth contact. Infants and children with diarrhea can become dehydrated more quickly than adults.

PREVENTION

Causes of Travelers’ Diarrhea (TD) in children are similar to those in adults (see Chapter 4). For young infants, breastfeeding is the best way to reduce the risk of foodborne and waterborne illness. Travelers should use only purified water for drinking, preparing ice cubes, brushing teeth, and mixing infant formula and foods. Scrupulous attention should be paid to handwashing and cleaning pacifiers, teething rings, and toys that fall to the floor or are handled by others. When proper handwashing facilities are not available, an alcohol-based hand sanitizer can be used as a disinfecting agent. However, alcohol does not remove organic material; visibly soiled hands should be washed with soap and water.

Travelers should ensure that dairy products are pasteurized. Fresh fruits and vegetables must be adequately cooked or washed well and peeled without recontamination. Bringing finger foods or snacks (self-prepared or from home) will reduce the temptation to try potentially risky foods between meals. Meat, fish and eggs should always be well cooked and eaten just after they have been prepared. Travelers should avoid food from street vendors.

MANAGEMENT OF DIARRHEA IN INFANTS AND YOUNG CHILDREN

Adults traveling with children should be counseled about the signs and symptoms of dehydration and the proper use of World Health Organization oral rehydration solutions (ORS). Immediate medical attention is required for an infant or young child with diarrhea who has signs of moderate to severe dehydration (Table 8-1), bloody diarrhea, fever higher than 38.5° C (101.5° F), or persistent vomiting. ORS should be provided to the infant by bottle or spoon while medical attention is being obtained.

Assessment and Treatment of Dehydration

The greatest risk to the infant with diarrhea and vomiting is dehydration. Fever or increased ambient temperature increases fluid losses and speeds dehydration. Parents should be advised that dehydration is best prevented and treated by use of ORS, in addition to the infant’s usual food (Table 4-20). Rice and other cereal-based ORS, in which complex carbohydrates are substituted for glucose, are also available and may be more acceptable to young children. Adults traveling with children should be counseled that sports drinks, which are designed to replace water and electrolytes lost through sweat, do not contain the same proportions of electrolytes as the solution recommended by WHO for rehydration during diarrheal illness.

ORS packets are available at stores or pharmacies in almost all developing countries. [See information below regarding ORS availability in the United States.] ORS is prepared by adding one packet to boiled or treated water. Travelers should be advised to check packet instructions carefully to ensure that the salts are added to the correct volume of water. ORS solution should be consumed or discarded within 12 hours if held at room temperature or 24 hours if kept refrigerated. A dehydrated child will drink ORS avidly; travelers should be advised to give it to the child as long as the dehydration persists. An infant or child who vomits the ORS will usually keep it down if it is offered by spoon in frequent small sips.

Children weighing less than 10 kilograms who have mild to moderate dehydration should be administered 60-120 mL ORS for each diarrheal stool or vomiting episode. Children who weigh 10 kg or more should receive 120-240 mL ORS for each diarrheal stool or vomiting episode. Severe dehydration is a medical emergency that usually requires administration of fluids by IV or intraosseous routes.

Dietary Modification

Breastfed infants should continue nursing on demand. Formula-fed infants should continue their usual formula during rehydration. They should receive a volume that is sufficient to satisfy energy and nutrient requirements. Lactose-free or lactose-reduced formulas are usually unnecessary. Diluting formula may slow resolution of diarrhea and is not recommended. Older infants and children receiving semisolid or solid foods should continue to receive their usual diet during the illness. Recommended foods include starches, cereals, yogurt, fruits, and vegetables. Foods that are high in simple sugars, such as soft drinks, undiluted apple juice, gelatins, and presweetened cereals, can exacerbate diarrhea by osmotic effects and should be avoided. In addition, foods high in fat may not be tolerated because of their tendency to delay gastric emptying. The practice of withholding food for 24 hours or more is inappropriate. Early feeding can decrease changes in intestinal permeability caused by infection, reduce illness duration and improve nutritional outcome. Highly specific diets (e.g., the BRAT [bananas, rice, applesauce, and toast] diet) have been commonly recommended; however, similar to juice-centered and clear fluid diets, such severely restrictive diets used for prolonged periods of time can result in malnutrition and should be avoided (2).

ORS packets are available in the United States from Jianas Brothers Packaging Company, 2533 Southwest Boulevard, Kansas City, Missouri 64108, USA (1-816-421-2880). In addition, Cera Products, 9017 Mendenhall Court, Columbia, Maryland 21045, USA (1-410-309-1000 or 1-888-Ceralyte;http://www.ceraproductsinc.com), markets a rice cereal rather than a glucose-based product, Ceralyte, in different flavors. ORS packets may also be available at stores that sell outdoor recreation and camping supplies.

Other Measures

Parents should be particularly careful to wash hands well after diaper changes for infants with diarrhea to avoid spreading infection to themselves and other family members.

Oral syringes that are available in most pharmacies for oral medications can be useful for the administration of ORS and can be included as part of the travelers’ health kit for young children.

The use of antimotility agents (e.g., loperamide, lomotil) in children younger than 2 years of age is not recommended. Because overdoses of these types of drugs can be fatal, they should be used with extreme caution in children. Side effects of these drugs in adults include opiate-induced ileus, drowsiness, and nausea. Lomotil has been associated with fatal overdoses and other severe complications, including coma and respiratory depression. Antinausea medications, such as promethazine and prochlorperazine, are not routinely recommended. They are contradicated for use in children less than 2 years of age. Fatal respiratory depression in children has been reported with use of promethazine. Children with an acute illness, including gastroenteritis and dehydration, are more susceptible to neuromuscular reactions, especially dystonias, associated with prochlorperazine, than adults. The extrapyramidal side effects associated with these medications can be confused with symptoms of other undiagnosed primary diseases associated with vomiting, such as Reye syndrome. These medications should not be routinely prescribed as empiric treatment for children with possible TD. Adults traveling with children should be fully counseled about the indications, dosage, frequency and possible side effects if these medications are prescribed.

Antibiotics

Few data are available regarding empiric administration of antibiotics for TD in children. Furthermore, the antimicrobial options for empiric treatment in children are limited. Trimethoprim-sulfamethoxazole (TMP/SMX) was previously used for empiric treatment of TD in children; however, its effectiveness has been reduced by widespread drug resistance and it is no longer routinely recommended. Fluoroquinolones are frequently used for the empiric treatment of TD in adults. The use of fluoroquinolones is not generally recommended for use in children and adolescents less than 18 years of age because of cartilage damage seen in animals tested. The only indication for fluoroquinolone use in children that has been approved by the Federal Drug Administration is for complicated urinary tract infections. The American Academy of Pediatrics suggests some special circumstances for fluoroquinlone use, including the treatment of gastrointestinal infection caused by multidrug-resistant Shigella species, Salmonella species, Vibrio cholerae, or Campylobacter jejuni. Although not FDA-approved, some travel medicine advisors have reported using 1-3 days of ciprofloxacin for treatment of TD in some older children. However, the routine use for empiric treatment for TD is not recommended. Tetracyclines can cause teeth staining if used in children less than 8 years of age (3).

In some studies, azithromycin has been found to be as effective as fluoroquinolones in treating TD in adults (4). In practice, some clinicians prescribe azithromycin either as a single dose or at 10 mg/kg for 3-5 days for empiric treatment. Flavored oral suspension of azithromycin is available. The suspension does not require refrigeration; however, it should be used within 10 days of mixing. The unreconstituted form of azithromycin has a longer expiration period. In certain circumstances, the unreconstituted form can be provided with clear instructions for preparation and may be useful for children traveling for longer than 10 days.

TABLE 8-1. Assessment of Dehydration Levels in Infants

Malaria

Malaria is one of the most serious, life-threatening diseases affecting pediatric international travelers. In the United States, 4,110 cases of malaria in US civilians were reported to CDC from 2000 through 2004. Of these cases, 572 (14%) occurred in children <18 years of age. Among children with malaria, 182 (32%) were 1 month to 5 years old, 126 (22%) were 6-9 years old, 146 (25%) were 10-14 years old, and 118 (21%) were 15-17 years old. The largest percentage of cases occurred in persons who were visiting friends and relatives.

Children with malaria can rapidly develop a high level of parasitemia. They are at increased risk for severe complications of malaria, including shock, seizures, coma, and death. Initial symptoms of malaria in children may mimic many other common causes of pediatric febrile illness and therefore may result in delayed diagnosis and treatment. Clinicians should counsel adults traveling in malarious areas with children to be aware of the signs and symptoms of malaria and to seek prompt medical attention if they develop.

Detailed information about malaria risk and chemoprophylaxis, as well as precautions for avoiding mosquito bites, is presented in Chapter 4. Medications used for infants and young children are the same as those recommended for adults except that doxycycline should not be given to children younger than 8 years of age. Atovaquone/proguanil (Malarone) should not be used for prophylaxis in children weighing less than 5 kg (11 lbs) because of lack of data on safety and efficacy. Pediatric doses for malaria chemoprophylaxis are provided in Tables 4-10 and 4-11. Pediatric doses of medications used for self-treatment are included in Table 4-12.

Because overdose of antimalarial drugs can be fatal, medication should be stored in childproof containers and kept out of the reach of infants and children. Mefloquine and chloroquine phosphate are manufactured in the United States in tablet form. Atovaquone/proguanil is available in pediatric tablet form. Pediatric doses should be calculated carefully according to body weight. Before departure, pharmacists can be asked to pulverize tablets and prepare gelatin capsules with calculated pediatric doses. Chloroquine, mefloquine, and atovaquone/proguanil have a bitter taste. Mixing the powder in a small amount of food or drink can facilitate the administration of antimalarial drugs to infants and children. Additionally, any compounding pharmacy can alter the flavoring of malaria medication tablets so that they are more willingly ingested by children. A list of compounding pharmacies is available athttp://www.iacprx.org/referral_service/index.html. Physicians should calculate the dose and volume to be administered based on body weight because the concentration of chloroquine base varies in different suspensions.

Insect and Other Arthropod Protection

Personal protection against mosquitoes, ticks, and biting flies is an important part of prevention against malaria, yellow fever, and other diseases for which no other prophylaxis is available, such as dengue fever (5,6). While outdoors, children should wear as much protective clothing (long sleeves and long pants) as they can tolerate. They should sleep in rooms with air conditioning or screened windows or under bed nets. Mosquito netting should be used over infant carriers. Clothing and mosquito nets can be treated with permethrin, a repellent and insecticide derived from chrysanthemum flowers that repels and kills ticks, mosquitoes and other arthropods. Permethrin remains effective through multiple washings. Clothing and bednets should be retreated according to product label. Permethrin should not be applied to the skin.

CDC recommends the use of repellents, with active ingredients registered with the United States Environmental Protection Agency (EPA), according to the product labels. In scientific studies, two registered products, DEET (N,N-dimethyl-m-toluamide) and picaridin, have been demonstrated to have a higher degree of efficacy than products containing other repellents. In recent studies, repellent products containing oil of lemon eucalyptus were tested against mosquitoes in the United States and were found to provide protection similar to low concentrations of DEET. Other products have been evaluated for repellent activity. However, they have not been as well studied as DEET and may not be safe for use in children. Most botanical products provide relatively limited or no protection.

There had been some concern about potential toxicity of DEET and controversy regarding the recommended concentration of DEET for pediatric use. In 1998, the EPA conducted an extensive review of DEET safety. The agency concluded that there is no evidence that DEET is toxic to infants and/or children. Additional evaluations have not demonstrated a link between seizures and topical use (7). The EPA has concluded that concentrations up to 30% can be used on children. DEET should not be used on infants younger than 2 months of age because of concern about increased skin permeability. The American Academy of Pediatrics supports this recommendation (8).

The concentration of DEET affects the duration of protection. Higher concentrations provide longer protection; however, the duration of protection reaches a plateau at approximately 30%-50%. In a laboratory study, a product with 23.8% DEET provided an average of 5 hours of protection (range 3-6 hours), and a product with 6.65% DEET provided an average of 2 hours of protection (range 1.5-2.8 hours). Duration of protection may be affected by the environmental temperature, sweating, and wind conditions (9).

The EPA recommends the following precautions when using insect repellents:

• Apply repellents only to exposed skin and/or clothing.
• Never use repellents over cuts, wounds or irritated skin.
• Do not allow young children to handle the product.
• When using repellent on a child, an adult should apply it to his or her own hands and then rub them on the child. Avoid the child’s eyes and mouth and apply sparingly around the ears.
• Do not apply repellent to children’s hands. (Children tend to put their hands in their mouths.)
• Use just enough repellent to cover exposed skin and/or clothing. Heavy application and saturation are generally unnecessary for effectiveness. If biting insects do not respond to a thin film of repellent, then apply a bit more.
• After returning indoors, wash treated skin with soap and water or bathe. This is particularly important when repellents are used repeatedly in a day or on consecutive days.

Products that contain repellents and sunscreen are generally not recommended because of the need to reapply sunscreen more frequently than repellent. Mosquito coils should be used with extreme caution in the presence of children to avoid burns and inadvertent ingestion (10).

Infection and Infestation from Soil Contact

Children are more likely than adults to have contact with soil or sand and therefore may be exposed to infectious stages of parasites present in soil, including ascariasis, hookworm, cutaneous larva migrans, trichuriasis, and strongyloidiasis. Children and infants should wear protective footwear and play on a sheet or towel rather than directly on the ground. Clothing should not be dried on the ground. Clothing or diapers dried in the open air should be ironed before use to prevent infestation with fly larvae (myiasis).

Animal Bites and Rabies

Worldwide, rabies is more common in children than adults. In addition to the potential for increased contact with animals, children are also more likely to be bitten on the head or neck, leading to more severe injuries. They are also less likely to report a bite. Children and their families should be counseled to avoid all stray or unfamiliar animals and to inform adults of any contact or bites. Animal exposure abroad is not limited to rural areas, since stray dogs are common in many urban areas. Children may approach or be unable to avoid animals. Mammal-associated injuries should be washed thoroughly with water and soap (and povidone iodine if available), and the child should be evaluated promptly for the need for rabies postexposure prophylaxis and other measures (see Chapter 4).

Air Travel

Injuries and deaths can occur in children held on adult laps during turbulence and nonfatal crashes. The American Academy of Pediatrics recommends that children should be placed in a rear-facing Federal Aviation Authority (FAA)-approved child-safety seat until they are at least 1 year old and weigh at least 20 pounds. Children older than 1 year of age and 20-40 pounds in body weight should use a forward-facing FAA-approved child safety seat, while children weighing more than 40 pounds can be secured in the aircraft seat belt (11). Air travel is safe for healthy newborns and infants; however, children with chronic heart or lung problems or with upper or lower respiratory symptoms at the time of travel may be at risk for hypoxia during flight, and a physician should be consulted before travel.

Ear pain can be very troublesome for infants and children during descent. Equalization of pressure in the middle ear can be facilitated by swallowing or chewing; infants should nurse or suck on a bottle. Older children can try chewing gum. Antihistamines and decongestants have not been shown to have benefit. There is no evidence that air travel exacerbates the symptoms or complications associated with otitis media (12,13).

Travel to different time zones, “jet lag,” and schedule disruptions can disturb sleep patterns in infants and children, as well as adults. Attempts to adjust sleep schedules 2-3 days before departure may be helpful. After arrival, children should be encouraged to be active outside during daylight hours to promote adjustment. Sedative medications may cause oversedation or paradoxical agitation, and melatonin may have effects on sexual development in infants and children. In general, these medications should be avoided in infants and children. Diphenhydramine can be useful for some children but, similar to any medication for sedation, should be administered as a test dose before travel to determine the effect on the individual child.

MOTION SICKNESS

Motion sickness can present as ataxia, dizziness, and nausea in children. Other symptoms include pallor and cold sweats. For symptomatic treatment of children, dimenhydrinate, 1-1.5 mg/kg per dose, or diphenhydramine, 0.5-1 mg/kg per dose, up to 25 mg, can be given 1 hour before travel and every 6 hours during the trip. Because some children have paradoxical agitation with these medicines, a test dose should be given at home before departure. Scopalamine causes potentially dangerous adverse effects in children and should not be used; prochlorperazine and metoclopramide should be used with caution in children (see page 524).

Accidents

VEHICLE-RELATED

Vehicle-related accidents are the leading cause of death in children who travel. While traveling in automobiles and other vehicles, children weighing less than 40 pounds should be restrained in age-appropriate car seats or booster seats (as above). These seats often must be carried from home, since availability of well-maintained and approved seats may be limited abroad. In general, children are safest traveling in the rear seat; no one should ever travel in the bed of a pick-up truck. Families should be counseled that many developing countries have cars without rear seatbelts.

DROWNING AND WATER-RELATED ILLNESS AND INJURIES

Drowning is the second leading cause of death in young travelers; close supervision is essential. Appropriate water safety devices such as life vests may not be available abroad, and families should consider bringing these from home. A variety of diarrheal and parasitic illnesses can be transmitted by swallowing even small amounts of fecally contaminated water, and other infections, such as schistosomiasis, result from skin contact with contaminated water. Thus, while in schistosomiasis-endemic areas (see Map 4-11), children should not swim in fresh, unchlorinated water and should be carefully supervised while being washed in a bathtub. Protective footwear is important to avoid injury in many marine environments.

OTHER INJURIES

Conditions at hotels and other lodging may not be as safe as those in the United States and accommodations should be carefully inspected for exposed wiring, pest poisons, paint chips, or inadequate stairway or balcony railings (see Chapter 6).

Altitude

Children are as susceptible to altitude illness as adults, and young children who cannot talk can show very nonspecific symptoms, such as loss of appetite and irritability (14). Young children may present with unexplained fussiness and change in sleep and activity patterns; older children may complain of headache or shortness of breath. Acetazolamide (Diamox) is not approved for pediatric use for altitude illness, but it is generally safe in children when used for other indications. Allergic reactions to acetazolamide are extremely rare, but the drug is related to sulfonamides and should not be used by sulfa-allergic persons, unless a trial dose is taken in a safe environment before travel (see Chapter 6).

Sun Exposure

Sun exposure and particularly sunburn before age 15 are strongly associated with melanoma and other forms of skin cancer. Exposure to UV light is highest near the equator, at high altitudes, during midday (10 a.m. to 4 p.m.), and where light is reflected off water or snow. Sunscreens (or sun blocks), either physical (titanium or zinc oxides) or chemical, at least SPF 15 and providing protection from both UVA and UVB, should be applied as directed, especially after sweating and water exposure. If both sunscreen and insect repellent are applied separately or as a combined product, the efficacy of the sunscreen is diminished by one third, and covering attire should be worn or time in the sun decreased accordingly. Hats and sunglasses also reduce sun injury to skin and eyes. Babies younger than 6 months of age require extra protection from the sun because of their thinner and more sensitive skin; severe sunburn for this age group is considered a medical emergency. Babies should be kept in the shade and wear clothing that covers the entire body; a minimal amount of sunscreen can be applied to small exposed areas, including the infant’s face and hands. However, in general, sunscreens are generally recommended for use in children older than 6 months of age (see Chapter 6).

Other General Considerations

Changes in schedule, activities, and environment can be stressful for children. Including them in planning for the trip and bringing along familiar toys or other objects can decrease these stresses. For children with chronic illnesses, decisions regarding timing and itinerary should be made in consultation with a health-care provider(s).

As for any traveler, insurance coverage for illnesses and accidents while abroad should be verified before departure. Consideration should be given to purchasing special travel insurance for airlifting or air ambulance to an area with adequate medical care. In case family members become separated, each infant or child should carry identifying information and contact numbers in their own clothing or pockets. Because of concerns about illegal transport of children across international borders, if only one parent is traveling with the child he or she may need to carry relevant custody papers or a notarized permission letter from the other parent.

Pediatric Travel Health Kit

In addition to the kit recommended for all travelers (see Chapter 2), parents should carry safe water and snacks; waterless, alcohol-based hand sanitizer; child-safe hand wipes; ORS packets; oral syringes for the administration of medications and ORS; diaper rash ointment; and a water- and insect-proof ground sheet for play outside. In addition, many countries may not provide medications and child-care products of the same type and quality as are available at home. In selected circumstances, rectal preparations of medications, such as acetaminophen; topical antibacterial antibiotics, such as mupirocin; and lice and scabies topical treatments may be useful. As a precaution, travelers with children should consider bringing additional items they might need, such as baby formula and medications specific to the child.

Useful Links

American Academy of Pediatrics. http://www.aap.org

REFERENCES

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10. American Academy of Pediatrics. Summer safety tips. http://www.aap.org/advocacy/releases/summertips.htm (accessed 26 March 2007).
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