More than 30 million people in the United States travel to resource-limited areas of the world each year. This global mobility may contribute to the spread of infectious diseases — such as influenza, measles, and meningitis — and may also put individual travelers at risk for malaria, typhoid, dengue fever and hepatitis. Despite these potential risks, a recent study conducted by the Division of Infectious Diseases at Massachusetts General Hospital (MGH) and published in the Journal of Travel Medicine found that 46 percent of travelers to resource-limited countries did not seek health advice or vaccinations prior to departure.
The researchers surveyed more than 1,200 international travelers departing the United States at Boston Logan International Airport. The study was the result of a broad-based collaboration between MGH, the Centers for Disease Control and Prevention (CDC), the Boston Public Health Commission, and officials from the Massachusetts Port Authority, which owns and operates Logan International Airport. Based on the results from this work, the CDC, travel medicine experts and Logan Airport officials hope to develop better tools to educate people about the public health risks associated with global travel.
Of those surveyed, 38 percent were traveling to countries described as low- and low-middle income by the World Bank’s World Development Report, yet 46 percent of those travelers did not seek health advice prior to departure. Foreign-born travelers — including those traveling to visit family and friends, and those traveling alone or for vacation — were the least likely to have researched health information. The most commonly cited reason for not pursuing health information was a lack of concern about potential health problems.
Of the 54 percent of travelers to resource-limited countries who did seek health information, the Internet was the most common source, followed by primary care practitioners (PCPs).
“These results suggest that the Internet and PCPs are two promising avenues for disseminating information about traveling safely,” says the study’s lead author Regina C. LaRocque, MD, MPH, of MGH’s Division of Infectious Diseases. “Offering online resources at the time of ticket purchase or through popular travel websites would likely reach a large audience of people in need of health advice.”
The rapid global spread of Severe Acute Respiratory Syndrome (SARS) in 2002-2003 and new influenza strains in 2009 exemplified the role played by travelers in disseminating infectious diseases. More recently, dengue fever — a tropical disease found mainly in the Caribbean, Latin America and Asia — has been reported in the southern United States. In India, an epidemic of Chikungunya — a viral infection characterized by fever, headache, weakness and joint pain — was spread to Italy by travelers.
“International travel is the primary way many infections traverse the world,” says Edward Ryan, MD, director of the Tropical and Geographic Medicine Center in the Division of Infectious Diseases at MGH and a senior author of the study. “What many people don’t realize is that, without seeking the correct health information, they are putting themselves at increased risk of infection, as well as creating a public health risk in their home communities after they return.”
This study was funded by CDC grants aimed at gathering demographic data on international travelers. Additional ongoing research on U.S. international travelers is being conducted through the Global TravEpiNet, a consortium of travel clinics coordinated by MGH that is focused on improving research and health information regarding international travel.
Ryan is an associate professor and LaRocque an assistant professor of Medicine at Harvard Medical School. Additional authors of the Journal of Travel Medicine study are Sowmya R. Rao, PhD, Athe Tsibris, MD, and Thomas Lawton of the Massachusetts General Hospital; M. Anita Barry, MD, MPH, of the Boston Public Health Commission; and Nina Marano, DVM, MPH, Gary Brunette, MD, and Emad Yanni, MD, of the Centers for Disease Control and Prevention.
Massachusetts General Hospital, established in 1811, is the original and largest teaching hospital of Harvard Medical School. The MGH conducts the largest hospital-based research program in the United States, with an annual research budget of more than $600 million. The hospital is home to major research centers in AIDS, cardiovascular research, cancer, computational and integrative biology, cutaneous biology, human genetics, medical imaging, neurodegenerative disorders, photomedicine, regenerative medicine, systems biology, transplantation biology.
