Description

Pretravel consultations are an important way to assess trip plans, determine potential health hazards, discuss risks and methods of prevention.

Epidemiology

Incidence
There were 1.33 billion international tourist travel arrivals in 2017 (CDC). Illness and injury are common during travel.

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 a thoracic or abdominal surgery.
    • If preexisting eustachian tube dysfunction, use of a vasoconstricting nasal spray immediately before air travel may lessen the occurrence of otitis or barotrauma (1).
    • See CDC Yellow Book for list of special considerations for travelers with chronic medical illnesses including cardiovascular diseases, pulmonary diseases, diabetes, and severe allergic reactions.
  • Special conditions (pregnancy, breastfeeding, disability or handicap, immunocompromised state, older age)
    • Flying is generally discouraged after the 36th week of pregnancy. Many airlines require a provider letter if flying after this time.
  • 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)
  • Cholera (not available in the United States)—observing safe food, water, sanitation, and hand washing recommendations while in affected countries will have virtually no risk of acquiring cholera.
  • Hepatitis A
  • Japanese encephalitis
  • Rabies—if immunoglobulin would be difficult to obtain, consider vaccination to simplify postexposure prophylaxis.
  • Tick-borne encephalitis (not available in U.S.)
  • Typhoid—highest risk in India, Pakistan, and Bangladesh. Do not give live oral vaccine to pregnant women, immunocompromised patients, or if antibiotics taken in the previous 72 hours (2).
  • 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).
• 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 (1).
    • 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.
  • Bed nets
  • Insecticides and repellants—reapply regularly.
    • DEET, Picaridin
    • Oil of lemon eucalyptus, IR3535, 2-Undecanone
• Zika virus
  • Single-stranded RNA virus of the Flaviviridae family, genus Flavivirus
  • Most infections are asymptomatic.
  • Pregnant women should avoid travel to any area with risk of Zika virus transmission. Vertical transmission can lead to congenital Zika. Congenital Zika sequelae can include microcephaly with brain anomalies and fetal loss.
• SARS-Coronavirus-2
  • Consider delaying or cancelling trips planned if case numbers are high in originating location or destination.
  • Check travel restrictions, including testing requirements, before you go.
  • Do not travel if you have any symptoms. Avoid contact with anyone who is sick.
  • Bring extra supplies, such as masks and hand sanitizer.
  • Wear a mask.
  • 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).
• 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)
  • Most common bacteria is enterotoxigenic Escherichia coli. Common viruses include norovirus, rotavirus, and astrovirus. Most common protozoa is Giardia (2).
  • Length—bacterial causes last 3 to 7 days if untreated. Viral lasts 2 to 3 days. Protozoal can last weeks to months if not treated.
  • 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 of the 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 <3 years or pregnant women) (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 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 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 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 16 mg/day)
      • Pediatric dose
      • Not recommended for children <6 years
      • 6 to 8 years—2 mg initial dose, followed by 1 mg after each loose stool (max 4 mg/day)
      • 9 to 11 years—2 mg after initial dose, followed by 1 mg after each loose stool (max 6 mg/day)
      • ≥12 years: Refer to adult dosing.
    • Diphenoxylate
      • 5 mg (2 tablets) TID or QID until control achieved (max 20 mg/day)
      • Pediatric dose: not recommended for children <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—can occur by itself or with AMS and HACE. Symptoms begin with shortness of breath on exertion and progress to shortness of breath at rest, weakness, and cough. Supplemental oxygen and immediate descent. HACE and HAPE can be fatal, although HAPE is more rapidly fatal (2).
  • Preventive measures
    • Ascend gradually—from low altitude to <9,000 feet in 1 day. >9,000 feet, don’t climb >1,600 feet per day. Plan an extra day for acclimatization every 3,300 feet (2).
    • In first 48 hours, avoid alcohol and only perform mild exercise.
  • Preventive medications
    • Recommended for those at high risk for AMS (based on rate of ascent or history of HACE or HAPE): Consider for those at moderate risk.
    • Acetazolamide —AMS/HACE prevention dose: 125 mg BID (250 mg BID if >100 kg); pediatric dose: 2.5 mg/kg q12h (2)
      • AMS treatment dose: 250 mg BID; pediatric dose: 2.5 mg/kg q12h; used as an adjunct to dexamethasone
    • Dexamethasone —usually reserved for treatment; prevention dose: 2 mg q6h or 4 mg q12h; should not be used for prophylaxis in pediatric patients (2)
      • AMS treatment dose: 4 mg q6h PO, IV, or IM (2)
      • HACE treatment dose: 8 mg once, 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
    • Children ages 2 to 12 years
    • Women, especially when pregnant, menstruating, or on hormones
    • People who get migraines
  • Prevention strategies
    • Avoidance of known triggers
    • Strategic positioning (front of car, overwing 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 1.0 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 information
  • Avoid contact with animals because bites and scratches may transmit rabies.
  • Discuss risks such as traffic accidents, alcohol misuse, personal assault, robbery, and water safety.
  • Check hotels or other sleeping locations for bed bugs on bedding and furniture.
  • Consider travel insurance (including coverage for evacuation).
  • Hand carry medications and supplies.
  • Include medications to manage exacerbations or complications of existing chronic diseases.
  • Avoid areas with known outbreaks of communicable disease. Reference the CDC Travelers’ Health Web site before travel.
  • The Department of State’s Smart Traveler Enrollment Program provides destination-specific travel alerts.