Description

Pretravel consultations help determine potential health hazards, allow the opportunity to discuss risks, and maximize prevention.

Epidemiology

Incidence
In 2022, >900 million international arrivals were recorded across the globe. In the United States, ~22 million international visitors arrived in 2021, whereas ~10 million Americans visited foreign countries around the world (figures been impacted by COVID-19). As more and more people begin to travel again, illness and injury will be increasingly common.

Risk Factors

Risks vary by destination, length of the trip, planned activities, age, and health status of the traveler.

• Traveler details
  • Past medical history (age, gender, medical conditions, allergies, medications)
    • Flying is contraindicated within 3 weeks of a myocardial infarction and within 10 days of thoracic or abdominal surgery. Consider nasal spray before air travel if there is preexisting eustachian tube dysfunction (1).
  • Special conditions (pregnancy, breastfeeding, disability or handicap, immunocompromised state, older age)
    • Flying is often discouraged after the 36th week of pregnancy.
  • Immunization history
  • Prior travel experience (previous malaria prophylaxis, experience with altitude, illnesses related to prior travel)
• Trip details
  • Itinerary (countries/specific regions, rural or urban; side trips); timing (length, season, time until departure); reason for travel; special activities (disaster relief, medical care, high altitude or climbing, diving, cruise ship, rafting, cycling, extreme sports)

General Prevention

• Routine vaccinations
  • Haemophilus influenzae type b; hepatitis B—for last minute travelers, can offer accelerated vaccine schedule for hepatitis A and hepatitis B with Twinrix or accelerated schedule for hepatitis B alone with Heplisav-B
  • Influenza
  • Measles, mumps, rubella—more common in countries without routine childhood immunization, including Europe
  • Meningococcal—outbreaks common in sub-Saharan Africa especially during the dry season (December through June); Saudi Arabia requires the quadrivalent vaccine for Hajj pilgrims. Hajj visas require vaccine to be administered ≥10 days and ≤3 years (≤5 years for conjugate vaccine) before arriving in Saudi Arabia (2).
  • Pneumococcal
  • Polio—wild poliovirus type 1 circulates currently in Afghanistan and Pakistan (2).
  • Rotavirus—common in developing countries; does not usually cause travelers’ diarrhea in adults, so vaccination is only recommended for children
  • Tetanus, diphtheria, pertussis
  • Varicella—more common in countries without routine childhood immunization
  • Zoster—stress may trigger reactivation.
  • Human papillomavirus (HPV)—sexual activity during travel may lead to HPV infection.
• Travel-specific vaccinations (destination dependent)
  • Hepatitis A
  • Japanese encephalitis—most of Asia and parts of Western Pacific; 2-dose series given 28 days apart but may be given as early as 7 days; it must be given at least 1 week prior to travel.
  • Rabies—if immunoglobulin would be difficult to obtain, consider vaccination to simplify postexposure prophylaxis.
  • Tick-borne encephalitis (not available in the United States) is endemic in European and Asian countries.
  • Typhoid—highest risk in India, Pakistan, and Bangladesh; do not give live oral vaccine to pregnant women, immunocompromised patients, or if antibiotics are taken in the previous 72 hours (2). Oral vaccination is available for ages ≥6 years, and injectable vaccination options are available for ages ≥2 years. Oral vaccination is given at least 1 week prior to travel via four capsules taken every other day. Infectible vaccination is given at least 2 weeks prior to travel as a single dose.
  • Yellow fever—highest risk in sub-Saharan Africa and the Amazon regions of South America; vaccination is not considered valid until 10 days after administration (2); approved for ages ≥9 months as a single dose which provides lifelong protection for most people
• Malaria prophylaxis
  • Based on destination, types of planned activities, and patient preferences; CDC has up-to-date recommendations.
  • Chloroquine-sensitive malaria (2),(3)
    • Chloroquine—begin 1 to 2 weeks prior to travel, continue 4 weeks after leaving malaria-endemic area; may increase QTc interval (particularly if given with other QTc-prolonging drugs); adult dose: 300-mg base (500-mg salt) orally once weekly; pediatric dose: 5 mg/kg base (8.3 mg/kg salt) orally once weekly (up to 300-mg base per dose)
    • Hydroxychloroquine—begin 1 to 2 weeks prior to travel, continue for 4 weeks after leaving malaria-endemic area; dosed weekly; adult dose: 310-mg base (400-mg salt) orally once weekly; pediatric dose: 5 mg/kg base (6.5 mg/kg salt) orally once weekly (up to 310 mg base per dose)
  • Chloroquine-resistant malaria (2),(3)
    • Atovaquone/proguanil—begin 1 to 2 days before travel and continue for 1 week after leaving malaria-endemic area; adult dose: 250 mg/100 mg atovaquone/proguanil PO daily; pediatric dose: Tablets contain 62.5 mg/25 mg atovaquone/proguanil hydrochloride; 5 to 10 kg: 1/2 pediatric tablet daily; 10 to 20 kg: 1 pediatric tablet daily; 20 to 30 kg: 2 pediatric tablets daily; 30 to 40 kg: 3 pediatric tablets daily; >40 kg: 1 adult tablet daily
    • Doxycycline—begin 1 to 2 days before travel and continue for 4 weeks after leaving malaria-endemic area; adult dose: 100 mg orally daily; pediatric dose: ≥8 years old 2.2 mg/kg up to adult dose of 100 mg daily
    • Mefloquine—begin 1 to 2 weeks before travel and continue for 4 weeks after leaving malaria-endemic area; has a number of drug interactions; not recommended for people with cardiac conduction abnormalities (especially ventricular arrhythmias), major psychiatric disorders, or seizures; adult dose: 228-mg base (250-mg salt) orally once weekly; pediatric dose: ≤9 kg: 4.6 mg/kg base (5 mg/kg salt) orally once weekly; 10 to 19 kg: 1/4 tablet once weekly; 20 to 30 kg: 1/2 tablet once weekly; 31 to 45 kg: 3/4 tablet once weekly; >45 kg: 1 tablet once weekly
• Protection against mosquitoes and ticks
  • Avoid areas of known outbreaks of communicable disease. Refer to the CDC travelers’ health Web site for updates.
  • Avoid peak exposure times and places. Mosquitoes may bite at any time of the day. Peak biting activity for vectors of some diseases (such as dengue, Zika, and chikungunya) is during daylight hours. Peak biting activity for vectors of other diseases (such as malaria, West Nile, and Japanese encephalitis) are most active in twilight periods (dawn and dusk) or after dark.
  • Wear appropriate clothing: Minimize exposed skin. Check for ticks. Use bed nets.
  • Insecticides and repellants—reapply regularly.
    • DEET, picaridin, oil of lemon eucalyptus, IR3535, 2-Undecanone
• Zika virus
  • Transmitted via mosquito bite (Aedes species) or via sexual intercourse; vaccinations are not currently available, but use preventative techniques such as mosquito repellants or wearing long clothing to avoid mosquito bites.
  • Most infections are asymptomatic. Pregnant women should avoid travel to any area with risk of Zika virus transmission. Women planning for pregnancy should consider waiting 2 months after returning from Zika-endemic area prior to conceiving.
• SARS-coronavirus-2
  • CDC recommends receiving COVID-19 primary series and boosters as recommended by traveler age group.
  • Check travel restrictions, testing, vaccination, and mask requirements of each destination before you travel.
  • Consider delaying or cancelling planned trips if case numbers are high in originating location or destination.
  • Do not travel if you have any symptoms. Avoid contact with anyone who is sick. Consider wearing masks in congested areas, especially indoor public transportation. Consider getting tested for COVID-19 ≤3 days prior to your departure and 3 to 5 days after your arrival back home. Bring extra supplies, such as masks and hand sanitizer. Respect physical distancing recommendations by staying at least 6 feet apart from others. Wash your hands often or use hand sanitizer (with at least 60% alcohol).
• Mpox
  • Since April 2022, there has been a recent rise in mpox cases; transmitted via contaminated fomites, skin lesions, or body fluids from an infected person; symptoms include flulike symptoms followed by a rash (vesiculopustular) and may have umbilication. CDC recommends vaccination prior to travel if travelers fall into high-risk populations, including the immunocompromised. Postexposure prophylaxis (PEP) is also available for those who have been exposed to mpox. Decrease risk of infection by avoiding congregate areas, practicing safe sex, and avoiding contact with those infected with mpox.
• Traveler’s diarrhea
  • Symptoms range from mild abdominal cramping and urgent loose stools to severe abdominal pain, fever, vomiting, and bloody diarrhea; differs from food poisoning in which preformed toxins are ingested in food; nausea and vomiting may both be present although usually resolve within 12 hours; approximately 80–90% bacterial, 5–8% viral, 10% protozoal (1)
  • High-risk areas include Asia, Middle East, Africa, Mexico, and Central and South America (2).
  • Intermediate-risk areas include countries in Eastern Europe, South Africa, and some Caribbean islands (2).
  • Strategies to minimize diarrhea (2)
    • Wash hands or use sanitizer prior to eating. Avoid raw or undercooked meat, fish or shellfish, salads, uncooked vegetables, unpasteurized fruit juices, or unpasteurized milk or milk products. Avoid unpeeled raw fruit. Peel it yourself if possible. Tap water may be unsafe for drinking, making ice, preparing food, washing dishes, or brushing teeth; use sealed bottled water if possible.
  • For high-risk patients—bismuth subsalicylate reduces incidence of travelers’ diarrhea by 50%; 2 oz of liquid or two chewable tablets QID (not recommended for children aged <3 years or pregnant women); note darkening of stool as a side effect (2).
  • Treatment based on severity of disease (2)
    • Mild—diarrhea is tolerable, not distressing, and does not interfere with activities; does not require antibiotics
    • Moderate—diarrhea is distressing and interferes with planned activities. Antibiotics such as fluoroquinolones, azithromycin, or rifaximin; loperamide can be used as a monotherapy.
    • Severe—incapacitating diarrhea; azithromycin is the preferred agent, although fluoroquinolones and rifaximin can also be used.
  • Antibiotic options for travelers’ diarrhea treatment
    • Azithromycin—1,000 mg one-time dose; if symptoms are not resolved in 24 hours, then continue daily dosing for 3 days. Alternate dosing is 500 mg daily for 3 days.
    • Ciprofloxacin—750 mg one-time dose; if symptoms are not resolved in 24 hours, then continue daily dosing for 3 days. Alternate dosing is 500 mg BID × 3 days.
    • Rifaximin—200 mg TID × 3 days
  • Adjunct medications
    • Loperamide—4 mg initially followed by 2 mg after each loose stool (max of 16 mg/day); pediatric dose: not recommended for children aged <6 years; 6 to 8 years old—2 mg initial dose, followed by 1 mg after each loose stool (max of 4 mg/day); 9 to 11 years old—2 mg after initial dose, followed by 1 mg after each loose stool (max of 6 mg/day); ≥12 years old: Refer to adult dosing.
    • Diphenoxylate: 5 mg (2 tablets) TID or QID until control is achieved (max of 20 mg/day); pediatric dose: not recommended for children aged <2 years; 0.3 to 0.4 mg/kg/day in 4 divided doses
• Altitude illness
  • More likely at an altitude of 8,000 feet (2,500 m) or higher, although can occur at lower altitudes; children and adults are equally susceptible. Factors that increase risk are elevation at destination, rate of ascent, and exertion (2).
  • Acute mountain sickness (AMS)—most common; typically presents with headache starting 2 to 12 hours after arrival; other symptoms include fatigue, loss of appetite, nausea, and vomiting; usually resolves within 24 to 48 hours of acclimatization (2)
  • High-altitude cerebral edema (HACE)—severe progression of AMS; rare, although most often associated with high-altitude pulmonary edema (HAPE); lethargy, drowsiness, confusion, ataxia; requires immediate descent (2)
  • HAPE—Symptoms include shortness of breath, weakness, and cough; requires supplemental oxygen and immediate descent.
  • Preventive measures
    • Ascend gradually. Avoid alcohol.
  • Preventive medications:
    • Recommended for those at high risk for AMS
    • Acetazolamide—AMS/HACE prevention dose: 125 mg BID (250 mg BID if >100 kg); pediatric dose: 2.5 mg/kg q12h; AMS treatment dose: 250 mg BID; pediatric dose: 2.5 mg/kg q12h; used as an adjunct to dexamethasone (2)
    • Dexamethasone—usually reserved for treatment; prevention dose: 2 mg q6h or 4 mg q12h; should not be used for prophylaxis in pediatric patients; AMS treatment dose: 4 mg q6h PO, IV, or IM; HACE treatment dose: 8 mg once and then 4 mg q6H PO, IV, or IM; pediatric dose: 0.15 mg/kg/dose q6h up to 4 mg (2)
    • Nifedipine—for prevention and treatment of HAPE; dose: 30 mg SR q12h (2)
    • Tadalafil—for prevention of HAPE only; dose: 10 mg BID (2)
    • Sildenafil—for HAPE prevention; dose: 50 mg q8h (2)
• Jet lag
  • Before travel, adjust sleep cycle (and possibly meal times) 1 to 2 hours earlier or later (depending on direction of travel) for several days prior to departure. Drink plenty of water to remain hydrated. Optimize sunlight exposure to destination. Sedative hypnotics (nonbenzodiazepine), such as zolpidem, can be useful. If using benzodiazepines, use short-acting agents, such as temazepam.
• Motion sickness
  • High risk individuals include children aged 2 to 12 years; patients who are pregnant, menstruating, or on hormones; patients who get migraines; and patients who are using certain medications.
  • Prevention strategies include avoiding known triggers and using strategic positioning (front of car, over wing of aircraft).
  • Treatment
    • Dimenhydrinate: pediatric dose: 1.0 to 1.5 mg/kg 1 hour before travel and every 6 hours during the trip
    • Diphenhydramine: pediatric dose: 0.5 to 1 mg/kg/dose up to 25 mg 1 hour before travel and every 6 hours during the trip
    • Scopolamine: transdermal patch to hairless area behind ear at least 4 hours prior to exposure and every 3 days as needed; should not be used in children
• Environmental hazards
  • Avoid walking barefoot (parasites can enter skin). Avoid swimming in freshwater where there is a risk for schistosomiasis or leptospirosis. Use sunscreen.
  • If scuba diving, avoid flying or altitude exposure >2,000 feet (2); ≥12 hours after surfacing from nondecompression dive; ≥18 hours after repetitive dives or multiple days of diving; 24 to 28 hours after a dive that required decompression stops
• Other considerations
  • Consider travel insurance, including coverage for evacuation.
  • Carry medications on carry-on or personal luggage.