Introduction to Travel Health & the Yellow Book
Rates of international travel have continued to grow substantially in the past decade. According to the World Tourism Organization, there were an estimated 880 million international tourist arrivals in 2009 throughout the world. In 2009, US residents made more than 61 million trips with at least one night outside the United States, an approximate 5% increase since 1999. Not only are more people traveling, but also they are seeking out areas that have rarely been visited in the past. The reasons for travel are also varied, including tourism, business, study abroad, research, visiting friends and relatives, ecotourism, adventure, medical tourism, mission work, or responding to an international disaster. Travelers range in age from very young infants to centenarians. Their health conditions are also diverse, including those who have preexisting medical conditions, are immunosuppressed, or are pregnant. The infectious disease risks that travelers face are dynamic—some travel destinations have become safer, while in other areas, new diseases have emerged and other diseases have reemerged.
The risk of becoming ill or injured during international travel depends on many factors, such as the region of the world visited, a traveler’s age and health status, the length of the trip, and the diversity of planned activities. The Centers for Disease Control and Prevention (CDC) provides international travel health information to address the range of health risks a traveler may face, with the aim of assisting travelers and clinicians to better understand the measures necessary to prevent illness and injury during international travel. This publication and the CDC Travelers’ Health website (www.cdc.gov/travel) are the two primary avenues of communicating CDC’s travel health recommendations.
HISTORY AND ROLES OF THE YELLOW BOOK AND THE INTERNATIONAL HEALTH REGULATIONS
CDC Health Information for International Travel (“The Yellow Book”) has been a trusted resource since 1967. Originally, it was a small pamphlet published to satisfy the International Sanitary Regulations’ requirements and the International Health Regulations (IHR), adopted by the World Health Organization (WHO) in 1951 and 1969, respectively. The purpose of the IHR is to ensure maximum security against the international spread of diseases, with minimum interference with world travel and commerce. A copy of the current IHR and supporting information can be found on the WHO website (www.who.int/csr/ihr/en).
The IHR (1969) were originally intended to help monitor and control 6 serious infectious diseases: cholera, plague, relapsing fever, smallpox, typhus, and yellow fever. Since then, the IHR have been amended several times, and were completely revised in 2005. Under the IHR (2005), states are required to notify WHO immediately in the event of identifying smallpox, severe acute respiratory syndrome (SARS), wild poliovirus, or novel influenza within their borders. Additionally, states are required to report to WHO any other event that signifies a public health emergency of international concern (PHEIC). A PHEIC is an event that constitutes a public health risk to other member states, with international consequences such as the spread of disease, and that potentially requires a coordinated international response, as in the case of 2009 pandemic influenza A (H1N1). This definition broadens the scope of the IHR to cover existing, new, and reemerging diseases, including emergencies caused by chemical, biological, or radiologic agents and the context surrounding these events. As a member state of WHO and signatory to the IHR (2005), the United States is responsible for following these reporting requirements.
In addition to reporting health events, the United States must also inform the public about health requirements for entering other countries, such as the necessity of being vaccinated against yellow fever. Some countries require all travelers to have an International Certificate of Vaccination or Prophylaxis (ICVP) documenting yellow fever vaccine administration as a condition for entry, while other countries require vaccination against yellow fever only if travelers arrive from a country where the yellow fever virus is known to circulate. The Yellow Book and the CDC Travelers’ Health website aim to communicate these requirements under the IHR (2005). Although this publication includes the most current available information, requirements can change. Current information must be accessed to ensure that these requirements are met; the CDC Travelers’ Health website (www.cdc.gov/travel) may be checked for regularly updated information.
The Yellow Book is written primarily for clinicians, including physicians, nurses, and pharmacists. Others, such as the travel industry, multinational corporations, missionary and volunteer organizations, and travelers themselves, can also find a wealth of information here.
This text is authored by subject-matter experts from within CDC and outside the agency. The guidelines presented in this book are evidence-based and supported by best practices. Internal text citations have not been included; however, a bibliography is included at the end of each section for those who would like to obtain more detailed information. In addition to the hardcopy text, a searchable online version of the Yellow Book can be found on the CDC Travelers’ Health website (www.cdc.gov/yellowbook).
NEW IN THE 2012 EDITION
The Yellow Book reflects the ever-changing nature of travel medicine. Each new edition notes the changes in global disease distribution, vaccine and medication guidelines, and new developments in preventing travel health risks. The CDC Travelers’ Health program and the CDC Foundation are pleased to partner with Oxford University Press, Inc., for the first time to publish the 2012 edition. Finally, the editorial team is always looking for ways to adapt the publication to meet the needs of its readers.
A few chapters contain important changes in the 2012 edition and are highlighted below. Some new sections in this edition include Special Considerations for US Military Deployments, Study Abroad, and Travel to Mass Gatherings.
Topics most commonly discussed in a pre-travel consultation, with the exception of infectious diseases, are found in Chapter 2. Just as in most pre-travel consultations, general issues concerning vaccine recommendations are discussed first, then self-treatable disease topics, and finally topics generally discussed when counseling travelers about healthy behaviors that may decrease risk of illness and injury. Chapter 3 now contains all infectious diseases, including vaccine-preventable diseases, in alphabetical order.
Country-specific yellow fever requirements and recommendations, and malaria transmission information and prophylaxis recommendations, have been combined into one section and are located at the end of Chapter 3.
Chapter 4, Select Destinations, highlights some popular tourist destinations and routes discussed by authors who have lived in or visited these areas. Some of these destinations have been updated from the 2010 edition, and some are new. The purpose of this chapter is to better orient travel health providers who may not have had the opportunity to travel to these destinations, frequented by many travelers, and from which many questions are generated. Similar to a guidebook, authors discuss the destination, along with the reality of various health risks, to aid clinicians in preparing travelers. These sections are editorial in nature, containing the author’s expressed opinions, and aim to present topics for consideration; they should not necessarily be taken as a prescription for pre-travel care.
Perspectives Editorial Sections
A continuing feature from the previous edition is the incorporation of editorial sections entitled Perspectives. These sections are noted by their distinctive icon and a box around the text. Although there is an increasing body of evidence-based knowledge in this new and growing field of travel medicine, there is also recognition that the practice of this specialty is not only science, but art as well. Thus, readers will notice a few sections that contain editorial discussions aiming to add depth and clinical perspective, as well as to discuss some controversies or differences in opinions and practice.
CONTACT INFORMATION FOR CDC
Questions, comments, and suggestions for CDC Travelers’ Health, including comments about this publication, may be made through the CDC-INFO contact center (toll-free at 800-CDC-INFO or email@example.com). Since CDC is not a medical facility, clinicians needing assistance with patients who are preparing for travel should consider referral to a travel clinic or a clinic listed on the International Society of Travel Medicine website (www.istm.org).
Clinicians with patient questions about post-travel health issues may consider referral to a clinic listed on the American Society of Tropical Medicine and Hygiene website (www.astmh.org) or to a medical university with infectious diseases capacity. Because of the clinical complexity of malaria, the CDC Malaria Branch offers clinicians assistance with the diagnosis or management of suspected cases of malaria. Clinicians can contact CDC’s Malaria Branch telephone hotline during business hours at 770-488-7788 or toll-free at 1-855-856-4713. After hours and on weekends and holidays, a Malaria Branch clinician may be reached by calling 770-488-7100.
- United Nations World Tourism Organization. UNWTO World Tourism Barometer. Madrid: United Nations World Tourism Organization; 2010 [cited 2010 Aug 2]. Available from: http://www.world-tourism.org/facts/wtb.html.
- US Department of Commerce. 2009 United States Resident Travel Abroad. Washington, DC: US Department of Commerce; 2010 [cited 2010 Nov 8]. Available from: http://tinet.ita.doc.gov/outreach.... (PDF)
- World Health Organization. International Health Regulations (2005). 2nd ed. Geneva: World Health Organization; 2008 [cited 2010 Nov 8]. Available from: http://www.who.int/ihr/9789241596664/en/index.html.