Chapter 1Introduction

David R. Shlim

Travel medicine is based on the concept of the reduction of risk. In the context of travel medicine, “risk” refers to the possibility of harm during the course of a planned trip. Some risks may be avoidable, and others may not. Vaccine-preventable diseases may be mostly avoidable, depending on the risk of the disease and the protective efficacy of the vaccine. Non-disease risks, such as motor vehicle accidents or drowning, account for a much higher percentage of deaths among travelers than infectious diseases.

For most travelers, the perception of risk colors their choice of destinations, activities, and health concerns. Travel health providers may know statistics for a given risk, but whether the risk is considered high or low depends on the perception of the traveler. For example, the risk of dying while trekking in Nepal is 15 deaths per 100,000 trekkers, but there is no objective way to determine whether this risk is high or low. When the manuscript that reported this risk of dying while trekking was peer reviewed, one reviewer wrote, “You need to emphasize that these data show how dangerous trekking actually is.” The other reviewer wrote, “You should make a point of stating that these data show how safe trekking is.”

The subjective sense of risk is based on one’s perception of risk ("15 per 100,000 means it’s dangerous”) and one’s tolerance for risk (“it may be 15 per 100,000, but it’s worth it”). This subjective sense of risk suffuses the field of travel medicine, from the travel health provider to the traveler, but it is rarely discussed. Some travelers canceled travel plans to Asia because of their fear of H5N1 avian influenza, even though the actual risk to travelers was extremely low. Other travelers plan to ascend Mount Everest, even though the risk of dying during an Everest climb is 1 in 40.

Regardless of the perception and tolerance of risk, the hazards associated with travel cannot be eliminated, just as the risks of staying home are not zero. Even the act of trying to prevent a risk—such as yellow fever—can lead to a fatal reaction to the vaccine in rare cases. Therefore, the goal in travel and in travel medicine should be skillfully managing risk, rather than trying to eliminate risk. The pre-travel visit is an opportunity to discuss risks and develop plans that minimize these risks. Each traveler may have individual concepts about the risks and benefits of vaccines, prophylaxis, and behavior modification.

Travelers should consider the psychological and emotional aspects of foreign travel. Culture shock can occur on either end of a journey: on arrival when one encounters an entirely strange new world, and on return when one’s own world may temporarily appear unfamiliar. Travelers with underlying psychiatric conditions should be cautious when heading out to a stressful new environment, particularly if they are traveling alone.

All travelers should contemplate the concept of commitment, which describes the fact that certain parts of a journey cannot easily be reversed. A person trekking into a remote area may have to realize that rescue, if available at all, may be delayed for days. A person who has a myocardial infarction in a country with no advanced cardiac services may have a difficult time getting to definitive medical care. If the traveler has already contemplated these concerns and accepted them, it will be easier to deal with them if they come to pass.

Travel helps break down the barriers between human beings around the world and enriches the lives of travelers. Despite the risks of travel, we should never lose sight of the benefits.