CDC Yellow Book 2024Preparing International Travelers
International travel is stressful. Stressors vary to some extent with the type of travel: short-term tourist travel likely creates the least stress, whereas frequent travel, humanitarian and disaster work, and expatriation cause the most. The stressors of travel can cause preexisting psychiatric disorders to recur, latent or undiagnosed problems to become apparent, and new problems to arise. In addition, jet lag, fatigue, travel during a pandemic, and work or family pressures can trigger anxiety and aggravate depressive symptoms in short-term travelers.
Occurrence of Mental Health Problems in Travelers
Data on the rate at which mental health problems occur in travelers are non-existent. Few data from clinical populations include a study of British diplomats, in which 11% of medical evacuations were nonphysical, or psychological in nature. In this study, among people evacuated for psychological reasons, 71% were in their 20s; the overall incidence for psychological evacuations was 0.3%, 41% of which were for depression. In a study of the US Foreign Service from 1982 through 1986, the incidence of psychiatric evacuations was 0.2%. Of these, 50% were for substance use or affective disorder, and evacuations for mania and hypomanic states accounted for 3%.
A study of psychiatric emergencies in travelers to Hawaii estimated a rate of 0.2% for tourists and 2% for transient travelers (those arriving in Hawaii with no immediate plans to leave) versus 1% for residents. The study listed diagnoses in this population, in order of decreasing frequency, as schizophrenia, alcohol abuse, anxiety reaction, and depression. Finally, researchers in a landscape analysis of travel-related psychosis generated a rough calculation of incidence rate for psychiatric hospitalization of tourists to a destination of high religious significance (Jerusalem) and noted 19.7 cases per 100,000; ≥3.5% of these were psychotic episodes without prior psychiatric history.
The Pretravel Consultation & Mental Health Evaluation
Travel health providers should include mental health screening in any pretravel consultation. Some groups especially warrant mental health screening, including people planning extended or frequent travel; participants in humanitarian or disaster relief work; and anyone intending to take up long-term or semipermanent residence in another country. Because travel medicine specialists rarely have mental health credentials, they should use a brief inquiry aimed at eliciting previously diagnosed psychiatric disorders. To introduce this portion of the consultation and to elicit the most cooperation, practitioners can enumerate that international travel is stressful for everyone and has been associated with the emergence or reemergence of mental health problems; the availability of culturally compatible mental health services varies widely; and laws regarding the use of illicit substances can be severe in some countries.
Ask travelers about indicators of overt or underlying mental health problems. Some areas to cover include whether the traveler previously experienced, was treated for, or was diagnosed with a psychiatric disorder, including any associated with prior travel, and the type of treatment (inpatient, outpatient, or medications) involved, if any. Also inquire about current psychiatric disorders and treatment and whether any members of their immediate family have serious mental health problems. In addition, ask travelers about current or past use of illicit substances and whether they have a formally diagnosed substance use disorder or if health care providers, friends, or family have suggested that the traveler might be using alcohol or other substances to excess.
In general, any history of inpatient treatment, psychotic episodes, violent or suicidal behavior, affective disorder (including mania, hypomania, or major depression), any treatment for substance use problems, and any current treatments warrant further evaluation by a mental health professional, preferably one experienced in handling problems related to international travel. On occasion, a patient’s mental status during the pretravel consultation will be notably abnormal, which also should prompt a referral to a mental health professional for further evaluation.
Challenges & Barriers to Healthy Travel
People with mental health issues might face several challenges and barriers to healthy travel. Be prepared to discuss and help the traveler manage the many of the following situations.
Mefloquine can cause neuropsychiatric side effects. Avoid prescribing mefloquine for malaria prophylaxis to patients with mental health issues. Please see the discussion of mefloquine in Sec. 5, Part 3, Ch. 16, Malaria.
Laboratory Monitoring of Medication Levels
For travelers who need routine laboratory testing to measure levels of lithium or other mood-stabilizing medications, clinicians should make them aware that they could face challenges in locating in-country laboratory facilities capable of this testing. Inform travelers that medication levels might fluctuate, particularly in environments with high ambient temperatures, because increased perspiration can lead to lithium toxicity, even on a consistent dose.
Medical Evacuation Insurance
Encourage travelers with mental health issues to consider purchasing international travel health and medical evacuation insurance policies that include coverage for psychiatric emergencies. Caution the traveler that many medical evacuation policies exclude psychiatric emergencies or evacuation for preexisting conditions. See Sec. 6, Ch. 1, Travel Insurance, Travel Health Insurance & Medical Evacuation Insurance, for details.
Mental Health Treatment
Long-term travelers or expatriates might have difficulty finding culturally compatible mental health treatment in the destination country. Counsel these travelers to seek assistance from a mental health professional with overseas experience.
Long-term travelers and expatriates might have difficulty obtaining refills of psychotropic medications while living overseas because availability, or even legality, of these drugs varies from country to country. Travelers should check with the country’s embassy or with a reputable in-country pharmacy or health care provider. As permitted by local laws, long-term travelers can have visiting friends or relatives, or other members of their company or organization, bring additional medication.
Currently sober travelers with substance use disorders might want to attend Alcoholics Anonymous (AA), Narcotics Anonymous (NA), or comparable meetings while overseas. AA and NA websites provide lists of meetings by country (see Sec. 3, Ch. 5, Substance Use & Substance Use Disorders, for more details). Travelers should confirm availability and language of meetings in advance.
Traveling with Psychotropic Medications
Customs regulations in some countries prohibit importation of medications used to treat mental health disorders. Customs officials might confiscate Schedule II drugs commonly used to treat attention deficit disorder (e.g., narcotics or stimulants, including amphetamines and methylphenidate). Rules vary by country, and travelers should check with the host country’s embassy before traveling. Health care providers, including pharmacists, in the destination country might be able to provide guidance to colleagues about medication restrictions.
Advise travelers to carry medications in their original containers, along with a letter from the prescribing physician indicating the medical reason for the prescription. Remind them that customs officials might seize their medication even if they adhere to these guidelines.
Stressors & Countermeasures
Nearly anyone visiting a foreign culture can experience culture shock. With culture shock, travelers lose their sense of mastery over their environment, and even routine tasks of everyday life become a challenge. Separation from family and support systems, unfamiliar behavior and language, and new threats to health and safety can aggravate culture shock. Foreknowledge of the phenomenon will help minimize the stress experienced, as will advance study of the culture, language, and health and security threats and possible countermeasures.
For most travelers, culture shock is a limited syndrome that does not usually go beyond variations in mood, energy, sleep, and attitudes toward the host country culture, like an adjustment disorder. Advise travelers that symptoms lasting >12 months could require assessment. In addition, suggest regular exercise, moderation in intoxicant use, adequate sleep and nutrition, and relaxation techniques (e.g., meditation, yoga, biofeedback) to help reduce the stress associated with international travel.
Jet lag is a common, manageable stressor for most international travelers. Travelers and travel health providers can find more details about this condition and what to do about it in Sec. 8, Ch. 4, Jet Lag.
Travel During a Pandemic
The coronavirus disease 2019 (COVID-19) pandemic has exacerbated travel-associated stress and concerns over becoming a possible conduit for disease transmission. Any steps travelers can take (see Box 2-13) to gain some measure of control over their personal health and to mitigate COVID-19–related risk factors might help assuage some of this stress. Recommended information resources for travelers include the Centers for Disease Control and Prevention COVID-19 website; the US Department of State website; and/or the embassy or ministry of health website for the traveler’s destination.
Advise travelers to review a variety of travel health insurance options and to consider purchasing policies that cover cancellations of travel and that provide for emergency medical care and medical evacuations due to COVID-19. Remind travelers that their travel experience could differ from what they had planned or expected; to have contingency plans in place in case of travel delays or interruptions; and to avoid crowded places, particularly in destinations where vaccine coverage is low or case rates and hospitalizations due to COVID-19 are high. For travelers with a low level of risk tolerance, those whose underlying health conditions place them at greater risk for severe COVID-19, or those who are considering travel with young, vaccine-ineligible children, it also might be appropriate to discuss and counsel delaying travel until some future date.
Box 2-13 Addressing potential stressors associated with travel during the coronavirus disease 2019 (COVID-19) pandemic: a checklist for travelers
☐ Be up to date with your COVID-19 vaccinations (including all recommended boosters) at least 2 weeks before travel.
☐ Do your research. Be prepared to comply with all requirements (e.g., pretravel vaccination and testing, post-arrival quarantine and providing contact information) for your international travel destination and for the United States; be aware that requirements can change between when you book your travel and when travel takes place.
☐ Get tested for COVID-19 before departure if required by your destination or recommended by current guidance.
☐ Obtain accepted formats for demonstrating proof of vaccination and negative test results; be prepared to provide before departure or on arrival.
☐ Identify (before travel, if possible) COVID-19 testing locations at your destination.
☐ Have contingency plans (e.g., alternative housing arrangements, reserve budget) in case of travel delays, cancellations, or itinerary modifications.
☐ Use personal protective measures (e.g., mask wearing) throughout your journey, including at places of congregation (e.g., airports, bus stations, train stations), on various modes of transportation (e.g., airplanes, buses, ships, trains), and at your destination.
Posttravel Mental Health Issues
Travelers who witness or who are directly involved in traumatic or life-threatening events can experience acute stress disorder (ASD) or posttraumatic stress disorder (PTSD). Examples of such events include motor vehicle accidents, assault or rape, terrorist incidents, natural disasters, or war. The work performed by humanitarian aid workers, disaster relief workers, and war correspondents increases their risk of developing subclinical or overt ASD or PTSD. For travelers who have had traumatic experiences, clinicians should inquire about recurrent, intrusive recollections, distressing dreams, and feeling as if the event is happening repeatedly; avoiding thoughts, feelings, activities, places, or people that lead to memories of the event; diminished interest in activities, inability to experience positive emotions, or an inability to remember significant details of the event; and difficulty sleeping or concentrating, irritability, or an exaggerated startle response.
Symptoms of PTSD can occur months or even years after an event. Thus, clinicians should educate returning travelers about the possibility of having such symptoms in the future. If there is concern about a traveler’s possible reaction to a traumatic event, refer them to a mental health professional.
People who have lived away from their home culture for extended periods of time (e.g., expatriate employees and their families) can experience reverse culture shock, which includes symptoms and a clinical course like that of culture shock. For example, first-year college students who spent their high school years abroad might find their “home” culture strange, compared with their fellow students who could be uninterested in their overseas experiences. Adults returning from abroad can experience a decreased standard of living or can find their “home” culture changed in unanticipated ways.
The following authors contributed to the previous version of this chapter: Thomas H. Valk
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