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Foreign Travel


Christopher Sanford

, MD, MPH, DTM&H, University of Washington;

Alexa Lindley

, MD, MPH, University of Washington School of Medicine

Last full review/revision Jul 2020| Content last modified Jul 2020
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Appropriate planning reduces the risks associated with travel, including foreign travel. Prior to travel, patients and their medical providers should review planned itineraries and relevant medical histories, required vaccinations Vaccinations Appropriate planning reduces the risks associated with travel, including foreign travel. Prior to travel, patients and their medical providers should review planned itineraries and relevant... read more , prophylactic measures against infections such as malaria Malaria Appropriate planning reduces the risks associated with travel, including foreign travel. Prior to travel, patients and their medical providers should review planned itineraries and relevant... read more and traveler's diarrhea Traveler’s diarrhea Appropriate planning reduces the risks associated with travel, including foreign travel. Prior to travel, patients and their medical providers should review planned itineraries and relevant... read more , and advice about personal protection measures, including those related to noninfectious threats such as road traffic crashes. For older travelers, the most common causes of death are heart attack and stroke; for other travelers, the most common cause of death is road traffic accidents.

About 1 in 30 people traveling abroad requires emergency care. Illness in a foreign country may involve significant difficulties. Many US insurance plans, including Medicare, are not valid in foreign countries; overseas hospitals often require a substantial cash deposit for nonresidents, regardless of insurance. Travel insurance plans, including some that arrange for emergency evacuation, are available through commercial agents, travel agencies, and some major credit card companies.

Directories listing English-speaking physicians in foreign countries, US consulates who may assist in obtaining emergency medical services, and information about foreign travel risks are available (see table Useful Contact for People Traveling Abroad Useful Contacts for People Traveling Abroad Useful Contacts for People Traveling Abroad ). Patients with serious disorders should consider pretravel contact or arrangements with an organization that offers medically supervised evacuation from foreign countries.

Certain infections are common when traveling to certain areas. Immunizations should be tailored to planned destinations, and advice regarding specific measures for preventing endemic and episodic infections should be given. Carrying medications to treat common infections (eg, upper respiratory infection, traveler's diarrhea) may be helpful.



Travelers should be current on all routine immunizations. Overview of Immunization Immunity can be achieved Actively by using antigens (eg, vaccines, toxoids) Passively by using antibodies (eg, immune globulins, antitoxins) A toxoid is a bacterial toxin that has been modified... read more Some countries require specific vaccinations (see table Vaccines for International Travel Vaccines for International Travel*, † Vaccines for International Travel*, † ). General travel and up-to-date immunization information is available from the Centers for Disease Control and Prevention (CDC) (Travelers’ Health: Vaccinations), and malaria chemoprophylaxis requirements are available from the CDC's malaria hotline (855-856-4713) and web site (Malaria and Travelers).



The COVID-19 pandemic currently active in mid-2020 has necessitated limitation of travel to and from various countries. Patients should be advised to check the website of their nation's health agency (eg, CDC in the US) for current recommendations.


Dengue fever Dengue Dengue is a mosquito-borne disease caused by a flavivirus. Dengue fever usually results in abrupt onset of high fever, headache, myalgias, arthralgias, and generalized lymphadenopathy, followed... read more is a mosquito-borne viral infection endemic to the tropical regions of the world in latitudes from about 35° north to 35° south. Outbreaks are most prevalent in Southeast Asia but also occur in the Caribbean, including Puerto Rico and the US Virgin Islands, Oceania, and the Indian subcontinent; more recently, dengue incidence has increased in Central and South America.

A vaccine for dengue is approved in several countries outside the US, but efficacy is only moderate and varies by dengue immune status, serotype, and patient age; studies are ongoing.

People traveling to endemic areas should try to prevent mosquito bites. Effective personal protection measures include applying DEET or picaridin to exposed skin, applying picaridin to clothing, and sleeping under a permethrin-treated mosquito net if sleeping quarters are not air conditioned (see CDC: Prevent Mosquito Bites). These measures also offer protection from other insect-transmitted diseases including Zika Zika Virus (ZV) Infections The Zika virus is a mosquito-borne flavivirus that is antigenically and structurally similar to the viruses that cause dengue, yellow fever, and West Nile virus. Zika virus infection is typically... read more and chikungunya Chikungunya disease Arbovirus (arthropod-borne virus) applies to any virus that is transmitted to humans and/or other vertebrates by certain species of blood-feeding arthropods, chiefly insects (flies and mosquitoes)... read more .



Malaria Malaria Malaria is infection with Plasmodium species. Symptoms and signs include fever (which may be periodic), chills, rigors, sweating, diarrhea, abdominal pain, respiratory distress, confusion... read more is endemic in Africa, India and other areas of South Asia, Southeast Asia, North and South Korea, Mexico, Central America, Haiti, the Dominican Republic, South America, the Middle East (including Turkey, Syria, Iran, and Iraq), and Central Asia. The CDC provides information about specific countries where malaria is transmitted (see Yellow Fever and Malaria Information, by Country ), types of malaria, and resistance patterns.


Schistosomiasis Schistosomiasis Schistosomiasis is infection with blood flukes of the genus Schistosoma, which are acquired transcutaneously by swimming or wading in contaminated freshwater. The organisms infect the... read more is common and is caused by exposure to freshwater in Africa, Southeast Asia, China, and eastern South America. Risk of schistosomiasis can be reduced by avoiding freshwater activities in areas where schistosomiasis is common. Asymptomatic travelers with freshwater exposure in endemic regions should be screened by serologic testing for antibody to the adult worm at 6 to 8 weeks following their most recent exposure. Alternately, travelers may elect to treat presumptively a potential exposure with praziquantel, 20 mg/kg orally 2 doses for 1 day and again at 6 to 8 weeks following the most recent exposure.

Traveler’s diarrhea

Traveler’s diarrhea Traveler’s Diarrhea Traveler’s diarrhea is gastroenteritis that is usually caused by bacteria endemic to local water. Symptoms include vomiting and diarrhea. Diagnosis is mainly clinical. Treatment is with ciprofloxacin... read more (TD) is the most common health problem among international travelers. TD is usually self-limited, typically resolving in 5 days; however, 3 to 10% of travelers with TD may have symptoms lasting > 2 weeks, and up to 3% of travelers have TD lasting > 30 days. TD lasting < 1 week requires no testing. For persistent TD, laboratory testing Testing Stool is 60 to 90% water. In Western society, stool amount is 100 to 200 g/day in healthy adults and 10 g/kg/day in infants, depending on the amount of unabsorbable dietary material (mainly... read more is done.

Self-initiated treatment is indicated for moderate to severe symptoms, especially if vomiting, fever, abdominal cramps, or blood in the stool are present. Treatment is with an appropriate antibiotic (eg, azithromycin, 500 mg or one gram once, or 500 mg once a day for 1 to 3 days). Additional measures include loperamide (except in patients with fever, bloody stools, or abdominal pain and in children < 2 years); replacement of fluids; and, in the elderly and small children, electrolytes (eg, oral rehydration solution).

Measures that may decrease the risk of TD include

  • Drinking and brushing teeth with bottled, filtered, boiled, or chlorinated water

  • Avoiding ice

  • Eating freshly prepared foods only if they have been heated to steaming temperatures

  • Eating only fruits and vegetables that travelers peel or shell themselves

  • Avoiding food from street vendors

  • Washing hands frequently

  • Avoiding all foods likely to have been exposed to flies

Prophylactic antibiotics are effective in preventing diarrhea, but because of concerns about adverse effects and development of resistance, they should probably be reserved for immunocompromised patients. One option is rifaximin, 200 mg once or twice a day.

Injury and death

Road traffic crashes are the most frequent cause of death of non-elderly international travelers. Travelers should at all times use a seat belt in vehicles and a helmet when cycling. Travelers should avoid motorcycles and mopeds and avoid riding on bus roofs or in open truck beds.

Drowning is another common cause of death while abroad. Travelers should avoid beaches with turbulent surf and avoid swimming after drinking alcoholic beverages.

Problems after returning home

The most common medical problem after travel is

The most common potentially serious diseases are

Some diseases become evident months after a traveler has returned home; a travel history with exposure risks is a useful diagnostic clue when patients present with a puzzling illness. The International Society of Travel Medicine ( and the American Society of Tropical Medicine and Hygiene ( have lists of travel clinics on their web sites. Many of these clinics specialize in assisting travelers who are ill after their return home.

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