Travel advice

INTRODUCTION — 

The clinical encounter for travel advice should include evaluation of the risk for adverse events based on the individual traveler's underlying medical conditions and travel plans (including the itinerary, anticipated activities, and potential exposures) [1-3].

Travel advice should include guidance about environmental exposures and behavioral precautions. In addition, managing risk for infection should be discussed, including administration of appropriate immunizations and assessing need for prophylaxis [4].

Beyond the information provided here, additional information can be obtained from the resources outlined below. (See 'Illness due to infection' below.)

Issues related to general travel advice will be reviewed here. Other travel-related issues are discussed separately:

●(See "Immunizations for travel".)

●(See "Travel advice for immunocompromised hosts".)

●(See "Travelers' diarrhea: Epidemiology, microbiology, clinical manifestations, and diagnosis".)

●(See "Travelers' diarrhea: Treatment and prevention".)

●(See "Prevention of malaria infection in travelers".)

REFERRAL FOR TRAVEL ADVICE

Whom to refer — Travelers who would most likely benefit from referral to a specialized travel clinic include [1]:

●Travelers with multiple comorbid conditions – Travelers with multiple comorbid conditions should undergo careful risk assessment. (See 'Review medical history and travel plans' below.)

●Immunocompromised hosts – Travel advice for immunocompromised hosts is discussed separately. (See "Travel advice for immunocompromised hosts".)

●Pregnant travelers – (See 'Pregnant travelers' below.)

Others who should be considered for referral include:

●Travelers returning to their country of origin to visit friends and relatives ("VFR" travelers) – VFR travelers may not realize they are at risk for illness associated with travel, so are less likely to seek travel advice [5-9]. As a result, preventable illnesses (such as malaria and typhoid fever) occur more commonly in this group than among other travelers.

●Travelers with complex itineraries – Travelers to regions with United Nations Human Development Index scores >95 percent (such as Canada, Australia, New Zealand, Japan, South Korea, and countries in western Europe), usually do not require specific travel advice; however, routine immunizations and health screenings should be current [1].

Travelers to other areas should be encouraged to seek pretravel advice. According to data collected by GeoSentinel (a network of clinical sites that perform surveillance of illnesses among ill travelers) between 2012 to 2021, Asia and sub-Saharan Africa were the most common regions where illnesses were acquired (32 and 25 percent, respectively) [9].

When to refer — Ideally, pretravel consultation should occur at least one month before travel, to allow time for thorough evaluation and for immunizations (some of which require more than one dose). For immunocompromised travelers, pretravel consultation as early as six months before travel may be beneficial because immune response may take longer to develop.

If this is not feasible, beneficial preventive measures and advice can be delivered even immediately before departure.  

In addition, discussion of potential health risks prior to booking travel arrangements may prompt patients to modify their travel plans.

REVIEW MEDICAL HISTORY AND TRAVEL PLANS — 

The pre-travel visit should begin with a detailed medical history and careful review of the travel plans.

●Medical history – Medical history should include [10]:

•Medical conditions (including pregnancy, immunosuppression, cardiopulmonary conditions, kidney function, neurologic illness, psychiatric illness, G6PD deficiency)

•Current medications

•Allergy history (especially to antimicrobial agents or vaccine components)

•Immunization history - If immunization records are not available and serologic testing is not possible, the traveler should be considered nonimmune.

●Travel plans – Travel plan details should be obtained, including [1]:

•Itinerary, including timing, destinations, and duration of travel

•Purpose of travel

•Planned activities and anticipated diet

•Types of accommodations

•Risk for potential exposures including arthropod bites, animal exposures, sexual contact

DISCUSS POTENTIAL HEALTH RISKS — 

Based on individual traveler characteristics and travel plans, assess travel-associated health risk. Forms of travel-associated illness include illness related to transportation, environmental exposures, and infection.

Thereafter, provide guidance for managing risk as appropriate.

Illness related to transportation

●Motor vehicle accidents – Road traffic accidents are estimated to cause nearly 25 percent of deaths among travelers [11]. Risk reduction measures include using seat belts, becoming familiar with local driving conditions, avoiding driving at night, avoiding alcohol consumption while driving, and avoiding rides in unmarked taxis or overcrowded buses.

●Air travel – Adults with certain preexisting conditions should be assessed prior to air travel. (See "Assessment of adult patients for air travel" and "Approach to patients with heart disease who wish to travel by air or to high altitude".)

Potential health concerns associated with air travel include:

•Deep venous thrombosis – Prolonged immobilization during flight is associated with increased risk for deep venous thrombosis, particularly in travelers with predisposing conditions. Risk reduction measures include maintaining hydration, mobility during flight, and use of compression stockings. (See "Pathogenesis, risk factors, and prevention of venous thromboembolism in adult travelers".)

•Reduced cabin oxygen – The reduced partial pressure of oxygen during flight may exacerbate certain medical conditions [12,13]. For patients with impaired cardiopulmonary function or other health problems, supplemental oxygen may be needed. (See "Evaluation of patients for supplemental oxygen during air travel".)

•Changes in barometric pressure – In the setting of upper respiratory tract infection, differential air pressures between the cabin and blocked eustachian tubes or sinuses may develop during ascent or descent, causing ear and/or sinus pain. (See "Ear barotrauma".)

•Jet lag – Jet lag may result when travel extends over multiple time zones. Management strategies are discussed separately. (See "Jet lag".)

●Cruise ships – Travelers subject to motion sickness may wish to bring medication for prevention and treatment. (See "Motion sickness".)

Outbreaks of gastrointestinal illness (particularly norovirus) have occurred on cruise ships [14]. Norovirus is not killed by alcohol or standard cleaning agents. Therefore, hand hygiene should consist of washing hands with soap and water (rather than use of alcohol-based hand disinfection), and contaminated environmental surfaces should be disinfected with bleach. (See "Norovirus".)

Outbreaks of respiratory illness (including COVID-19, influenza, and legionellosis) have also occurred on cruise ships. (See 'Respiratory hygiene' below.)

Illness associated with environmental exposure — Risks associated with certain environmental exposures may raise additional issues for evaluation and counseling.

●High altitude illness – For travelers to high altitudes, general preventive measures include ascending gradually, sleeping at lower altitudes with day hikes to higher altitudes, and minimizing alcohol consumption [15]. Prophylactic pharmacologic therapy may be considered to expedite acclimatization. (See "High-altitude illness: Physiology, risk factors, and general prevention", section on 'Prophylactic medication: Who needs it and what to give'.)

Patients with cardiopulmonary disease should be evaluated and counseled as outlined separately. (See "Approach to patients with heart disease who wish to travel by air or to high altitude" and "Evaluation of patients for supplemental oxygen during air travel".)

●Scuba diving – Advise individuals who have gone scuba diving to wait 12 to 48 hours before boarding an aircraft to avoid developing decompression sickness [16]. Other issues related to underwater diving are discussed separately. (See "Complications of SCUBA diving".)

●Wilderness travel – For individuals planning travel in outlying areas away from medical access and who are subject to potential environmental and exercise-related stresses, offer individualized guidance [17].

●Travel to farms – Travelers to farms may have increased risk for infection associated with animal exposure, including contact with raw eggs, unpasteurized dairy products, and meat or poultry. Hand hygiene is important for reducing transmission (table 1). (See "Causes of acute infectious diarrhea and other foodborne illnesses in resource-abundant settings".)

●Heat exposure – Heat exposure is an increasing problem globally. Heat risk can be mitigated by using heat alerts, limiting exposure, using cooling options, and developing heat plans. (See "Climate emergencies", section on 'Managing heat risk'.)

●Air pollution – Air pollution can cause adverse cardiopulmonary health effects for travelers [18]. Individuals with co-morbidities may be particularly affected and may reduce exposure by wearing facemasks outdoors and exercising indoors. (See "Overview of health effects of climate change".)

Illness due to infection — According to data collected by GeoSentinel (a network of clinical sites that perform surveillance of illnesses among ill travelers) between 2012 to 2021, the most common syndromic diagnoses included gastrointestinal, febrile, and dermatologic illnesses [9].

Resources for assessing risk of infection by destination include:

●The United States Centers for Disease Control and Prevention (CDC) website. This site includes an online version of Health Information for International Travel and updates on travel-related infections [9].

●GlobalTravEpiNet has web-based tools for providers and patients based on CDC recommendations.

●Websites with travel information maintained in the United Kingdom include the United Kingdom National Travel Health Network and Centre (NaTHNaC), and the related site Travel Health Pro.

Modes of transmission — Travel-associated infections may be acquired via enteral, vector-borne, respiratory, contact, animal, sexual, and/or bloodborne exposures:

●Unclean water or undercooked food – Infections transmissible by contaminated food and water include travelers' diarrhea, enteric fever, salmonellosis, shigellosis, Campylobacter infection, hepatitis A and E, norovirus, giardiasis, and others.

●Arthropod bites – Mosquito-borne infections include malaria, dengue fever, chikungunya, Zika virus infection, yellow fever, Japanese encephalitis, and others. Tick-borne infections include rickettsial infection, tick-borne encephalitis, Lyme disease, and others.

●Respiratory transmission – Respiratory viruses (such as influenza, COVID-19, and others) may be via droplets or aerosols through the air.

●Skin contact – Parasitic infections (such as cutaneous larva migrans, hookworm infection, strongyloidiasis, and others) may be transmitted by walking barefoot on contaminated sand or soil. Schistosomiasis and leptospirosis may be transmitted by contact with fresh water.

●Animal exposure – Animal bites or scratches may be associated with transmission of rabies (via dogs, bats, and other mammals) [19-21].

●Sexual contact – Sexually transmitted infections include human immunodeficiency virus (HIV), herpes, syphilis, gonorrhea, chlamydia, hepatitis (A, B, or C), Zika virus infection, mpox, and others [22-25].

●Bloodborne exposure – Infections transmitted via bloodborne exposure include HIV, hepatitis B and C, and others.

Behavioral precautions to reduce risk of infection are outlined below. (See 'Behavioral precautions' below.)

Tools for reducing risk of infection — Tools for reducing risk of infection include behavioral precautions, administration of immunizations, and instructions for malaria prophylaxis.

Behavioral precautions

Water and food — In areas where sanitation and personal hygiene may be poor, advise travelers to avoid consuming tap water, ice made from tap water, and raw foods rinsed with tap water (table 2). (See "Travelers' diarrhea: Treatment and prevention", section on 'Food and drink selection'.)

●Water and other beverages – Water may be consumed if it has been boiled, treated, or bottled. If safe drinking water is not available, water may be disinfected by boiling, halogenation, or filtering (table 2). Carbonated beverages, beer, wine, and drinks prepared with boiled water are generally considered to be free of pathogens. Drinks should be requested without ice.

●Food – Food should be eaten well-cooked and while still hot (table 2). Fresh produce that is washed in safe water and peeled by the traveler may be eaten. Unpasteurized dairy products and undercooked fish or meat should be avoided, as should food from street vendors given potential risk for contamination.

Vector avoidance — Advise travelers to areas where malaria or other arthropod-borne infections are endemic on measures to minimize arthropod bites. (See "Prevention of arthropod bites: Repellents and other measures".)

In general, precautions for prevention of mosquito bites include:

●Avoiding outdoor exposure during mosquito feeding time (between dusk and dawn for malaria, Japanese encephalitis, and West Nile virus; during the daytime for dengue, chikungunya, Zika, and yellow fever)

●Wearing clothing that reduces the amount of exposed skin (eg, long sleeves and pants)

●Treating fabrics (including clothes) with insecticides/acaricides

●Sleeping in accommodations with screened windows and doors, air conditioning, or bed netting (impregnated with pyrethroid, if feasible)

●Use of repellent

Additional precautions for prevention of tick-borne illness include:

●Avoidance of walking in scrub or tall grass

●Wearing closed footwear and tucking in long pants

●Checking for ticks daily (See "Evaluation of a tick bite for possible Lyme disease", section on 'Technique for tick removal'.)

Respiratory hygiene — Measures for prevention of respiratory viruses include vaccinations, mask-wearing, and frequent handwashing.  

Swimming and beaches

●Walking barefoot – Advise travelers about the risks of walking barefoot or in loose-fitting footwear on beaches or soil that may be contaminated with human or canine feces; such exposure may lead to contact with parasite larvae.

●Marine envenomation – Use of rubber-soled swimming shoes reduces risk for marine envenomation. (See "Marine envenomations from corals, sea urchins, fish, or stingrays".)

●Fresh water – Advise travelers to avoid contact with fresh water (such as swimming or wading) in areas where risk for schistosomiasis or leptospirosis is possible.

●Sun protection – Advise travelers to wear sun blocking agents with ultraviolet A and B protection. (See "Selection of sunscreen and sun-protective measures".)

Animal avoidance — Advise travelers against approaching animals; rabies is a potential risk from animal bites and scratches.

For travelers to areas where rabies is endemic, counseling should include the following [26,27]:

●Among travelers, dogs are the main source of rabies; other sources include bats, cats, and monkeys. Individuals who work with animals (veterinarians, animal handlers, field biologists) are at increased risk for rabies.

●Activities that confer risk for rabies infection include camping and spelunking.

●Children should be supervised closely around animals.

●Individuals with a bite or scratch should washed the area immediately with soap and water, then seek immediate medical care including postexposure vaccination as soon as possible (even if previously vaccinated). If vaccination is not locally available, be prepared to travel to another area or return home to receive treatment. (See "Rabies immune globulin and vaccine", section on 'Post-exposure prophylaxis'.)

Sexual activity — Caution travelers about sexual activity, especially in areas with high prevalence of HIV, hepatitis B, mpox, and antimicrobial-resistant infections (such as multidrug-resistant gonorrhea or Shigella species) [22-25].

For individuals who will be sexually active during travel, discuss preventive measures including barrier protection, pre-exposure prophylaxis, and postexposure prophylaxis. (See "Prevention of sexually transmitted infections".)

Persons who have new sexual partners during travel should be screened for sexually transmitted infections on their return. (See "Screening for sexually transmitted infections".)

Bloodborne exposures — Advise travelers to avoid potential bloodborne exposures (such as injections, piercings, tattoos, shared razors).

Immunizations — Categories of immunizations for travelers include those that are part of routine prevention, those that are required for travel, and those that are recommended based on the risk of exposure to vaccine-preventable diseases. These issues are discussed in detail separately. (See "Immunizations for travel".)

Malaria prophylaxis — Issues related to malaria prevention include mosquito avoidance and chemoprophylaxis. These are discussed in detail separately. (See 'Vector avoidance' above and "Prevention of malaria infection in travelers".)

Management of diarrheal illness — Issues related to prevention and management of travelers' diarrhea, including supportive care and the limited role for antibiotics, are discussed separately. (See 'Water and food' above and "Travelers' diarrhea: Treatment and prevention".)

Pregnant travelers — For pregnant travelers, considerations warranting particular attention include:

●Risk of air travel – Air travel in pregnancy is discussed in detail separately. (See "Prenatal care: Patient education, health promotion, and safety of commonly used drugs", section on 'Airline travel'.)

●Malaria prophylaxis – Malaria infection can be life-threatening for mother and fetus [28-31]. (See "Prevention of malaria infection in travelers", section on 'Pregnant travelers'.)

●Risk of infection

•Zika virus infection – Zika virus infection has been associated with congenital microcephaly and fetal losses among women infected during pregnancy; it has been advised that pregnant women consider postponing travel to areas where Zika virus transmission is ongoing. (See "Zika virus infection: An overview".)

•Oropouche virus infection - Vertical transmission of Oropouche virus may be associated with adverse pregnancy outcomes [32]. Pregnant persons should consider deferring travel to areas experiencing outbreaks of Oropouche virus disease in the Americas. (See "Emerging viruses", section on 'Oropouche virus disease'.)

ADDITIONAL ITEMS FOR DISCUSSION

Travel preparation

●Medications – Advise travelers to bring sufficient medications and supplies for the duration of travel, kept in carry-on luggage. Extra supplies of prescription medications can also be provided in case there are unexpected delays in returning home. In general, travelers should avoid purchasing medication in resource-limited or poorly regulated settings.

Travelers should carry a list of medications with dosages, as well as allergy history and any other important medical information. Those requiring additional equipment, such as needles and syringes, should carry a letter of medical necessity from their health care provider.

●Insurance – Advise travelers to consider travel health and medical evacuation insurance.

●Obtaining local care – Advise travelers with complex medical conditions to identify health care providers or clinics that can provide care in destination countries, if feasible.

Indications for immediate medical attention — Advise travelers to seek immediate medical attention in the following circumstances [1]:

●Serious injury

●Bloody diarrhea that does not respond to treatment

●Diarrhea associated with dehydration that does not respond to oral rehydration

●Unexplained fever, especially in a region where malaria is endemic

●Sexual assault

Travelers who have travel health insurance or evacuation insurance often have access to a 24-hour hotline to help identify sources of health care while traveling.

SOCIETY GUIDELINE LINKS — 

Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Travel medicine".)

INFORMATION FOR PATIENTS — 

UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or email these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topics (see "Patient education: Staying healthy when you travel (The Basics)" and "Patient education: Vaccines for travel (The Basics)" and "Patient education: Travelers' diarrhea (The Basics)")

●Beyond the Basics topics (see "Patient education: General travel advice (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Referral for travel advice – Travelers who would benefit most from referral to a specialized travel clinic include those with multiple comorbid conditions, immunocompromised hosts, and pregnant travelers. Others who should be considered for referral include those returning to their country of origin to visit friends and relatives and those with complex itineraries. (See 'Referral for travel advice' above.)

●The pre-travel visit

•Review medical history and travel plans – The pre-travel visit should begin with a detailed medical history and careful review of the travel plans (including the itinerary, anticipated activities, and potential exposures). (See 'Review medical history and travel plans' above.)

•Discuss potential health risks – Based on individual traveler characteristics and travel plans, identify and discuss potential health risks. (See 'Discuss potential health risks' above.)

●Forms of travel-associated illness – Forms of travel-associated illness include illness related to transportation, environmental exposure, and infection.

•Illness related to transportation – Motor vehicle accidents are an important cause of travel-related illness. Health concerns associated with air travel include deep venous thrombosis and complications associated with reduced cabin oxygen or changes in barometric pressure during flight. Health concerns associated with cruise ship travel include motion sickness and outbreaks of gastrointestinal and respiratory illness. (See 'Illness related to transportation' above.)

•Illness related to environmental exposure – Risks associated with certain environmental exposures may raise additional issues for evaluation and counseling; these include exposure to high altitudes, remote wilderness areas, farms, and scuba diving. (See 'Illness associated with environmental exposure' above.)

•Illness due to infection – Travel-associated infections may be acquired via enteral, vector-borne, respiratory, contact, animal, sexual, and/or bloodborne exposures. (See 'Illness due to infection' above.)

●Tools for reducing risk of infection – Tools for reducing risk of infection include behavioral precautions, administration of immunizations, and instructions for malaria prophylaxis.

•Behavioral precautions – Behavioral guidance includes precautions related to water and food (table 2), vector avoidance, respiratory hygiene, swimming and beaches, animal avoidance, sexual activity, and bloodborne exposures. (See 'Behavioral precautions' above.)

•Immunizations – Immunizations for travelers are discussed separately. (See "Immunizations for travel".)

•Malaria prophylaxis – Malaria prophylaxis is discussed separately. (See "Prevention of malaria infection in travelers".)

●Management of diarrheal illness – Issues related to prevention and management of travelers' diarrhea are discussed separately. (See "Travelers' diarrhea: Treatment and prevention".)