Travel epidemiology. WHO perspective

International travel is undertaken by large, and ever increasing numbers of people for professional, social, recreational and humanitarian purposes, and this upward trend looks set to continue. Travelers are exposed to a variety of health risks of the unfamiliar environment of the visited area. The risk of exposure is determined by destination, duration of the visit, purpose of the visit, behavior of the traveler and underlying physical and biological status of the traveler. However, most risks can be minimized by suitable precautions taken before, during and after travel. Travelers can themselves, also, easily introduce any infectious agents they may harbor to the visited area. Many infectious diseases have been introduced in many parts of the world through travel and trade. Travel has been identified as a prime factor in the global spread of infectious diseases. In a world of rapid air travel, no country is safe from infectious diseases. An outbreak in one country can easily and rapidly be transmitted across long distances to affect other countries through travel and trade. The World Health Organization devotes great attention to prevention and control of global spread of infectious diseases and minimizing the negative effect of international travel on health. The main strategies of the World Health Organization for minimizing the negative effects of expanding travel on global health security include developing the necessary strategies, rules and regulations; strengthening global communicable diseases surveillance and response; dissemination of related information throughout the world and strengthening national capacity for communicable diseases surveillance and response.