BIRMINGHAM, AL — Homer claimed the journey is the thing, but a study led by a UAB (University of Alabama at Birmingham) researcher suggests the destination matters most, at least when predicting the most likely diagnoses for ill travelers returning from the developing world.

The worldwide collaborative study — based on clinical data collected from more than 17,000 travelers ill enough to see a physician after returning home — formalizes anecdotal theories on trends related to travel disease and also underscores the value of global tracking as bird flu, SARS and other emerging infections loom.

The information, used by study authors to outline trends associating diseases with particular geographic regions, was collected through GeoSentinel, an established network of International Society of Travel Medicine-member clinics.

The study is published in Thursday’s (January 12) issue of The New England Journal of Medicine.

“This information gives us a blueprint of what to look for when it comes to diagnosing sick travelers, based on where they have been,” said lead author David O. Freedman, M.D., director of the University of Alabama at Birmingham Travel Medicine Clinic. “Doctors — travel medicine specialists in particular — can use the destination-specific differences we’ve found to guide the diagnosis and treatment of ill travelers … meaning they can order the correct tests and begin the correct therapy while waiting for confirmation.”

“The data also will be used to enhance information available to travelers on the Center for Disease Control and Prevention’s Travelers Health Web pages, one of the most widely used resources on CDC’s Web site,” said co-author Martin Cetron, M.D., director of the Division of Global Migration and Quarantine at the CDC.

“In a world where global travel is increasingly more common and tens of millions of people from industrialized nations travel to the developing world each year for commerce, research, education, missionary and military purposes, it is more obvious than ever that travelers should seek pre-travel consultation at a specialized travel clinic before travel and especially after they travel, if they become ill,” said co-author Phyllis Kozarsky, M.D., professor of medicine at Emory University.

TRENDS AMONG ILL TRAVELERS

Researchers used travel-related illness data collected from sick travelers between June 1996 and August 2004 with travel exposures from 230 countries to compare the frequency of occurrence of a wide spectrum of diseases, including well-known travel illnesses such as malaria and dengue fever, rickettsial infection (primarily transmitted by ticks), skin disorders, stomach problems, parasitic infections and respiratory disorders.

They concluded that a traveler’s destination is associated with the probability of the diagnosis of certain diseases. Some significant trends are based on regional differences:

• Among travelers presenting to GeoSentinel sites, fevers with only generalized symptoms occurred disproportionately among those returning from sub-Saharan Africa or Southeast Asia, acute diarrhea among those returning from south central Asia, and dermatologic problems among those returning from the Caribbean or Central or South America.
  
  
• Among specific diagnoses, malaria was one of the three most frequent causes of systemic fever-related illness among travelers from every region, although travelers from every region except sub-Saharan Africa and Central America had confirmed or probable dengue more frequently than malaria.
  
  
• Among travelers returning from sub-Saharan Africa, rickettsial infection, primarily tick-borne spotted fever, occurred more frequently than typhoid or dengue fever.
  
  
• Travelers from all regions except Southeast Asia presented with parasite-induced diarrhea more often than with bacterial diarrhea.

GeoSentinel, co-founded by Freedman, Kozarsky and Cetron, is a collaboration between the International Society for Travel Medicine and the CDC. It is a communications and data-collection network of 30 travel/tropical medicine clinics and 120 associated network members operating on six continents.

U.S. AND GLOBAL IMPLICATIONS

“Surveillance and detection is one of the three main pillars of our national strategy for pandemic influenza,” Freedman said. “Travel clinics such as the GeoSentinel sites are situated ideally, to effectively detect emerging infections of potential global impact at their point of entry and to track trends in travel-related morbidity.”

“This network is especially important for early detection and rapid response as well as sharing information with the World Health Organization and health ministries throughout the world,” Cetron added. “Networks such as these are widely recognized to be a vital part of surveillance designed to promote global health and security as envisioned by new International Health Regulations recently adopted by the World Health Assembly.”

Using experience gained during the 2003 SARS outbreaks, GeoSentinel has been gearing up with new sites in Asia to prepare for avian influenza and will continue to monitor disease trends in travelers and detect emerging infections, he added.

The electronic communications infrastructure established through GeoSentinel recently helped identify imported traveler-related cases and outbreaks of SARS from multiple locations, leptospirosis from Borneo, Hantavirus from Chile, Hajj meningitis from Singapore and the first-ever dengue from Easter Island.

Editor’s Note: We are the University of Alabama at Birmingham (UAB), not to be confused with the University of Alabama, a separate, independent campus in Tuscaloosa, Alabama. Please use UAB on second reference.