Report from the Asian-Pacific Travel Medicine (APTM) Meeting

Karl Neumann, MD, FAAP

Bangkok, Thailand. Travel health professionals often say that there is more to keeping travelers healthy than "giving shots and prescribing pills." But, in fact, too often the "more" in that message does not come through loud and clear to travelers. "More" needs to be done to emphasize that disseminating information is the cornerstone of travel medicine and that immunizations and medications supplement that information. This was the consensus of several well-known travel medicine specialists who spoke at the APTM in November. The meeting attracted almost 600 individuals from several dozen countries. Many of the speakers were ISTM members.

In many parts of the world, both developed and developing, much of travel medicine is practiced by health care professionals not well versed in the field and who are unaffiliated with local or international travel medicine groups. Most of these practitioners limit their services to providing immunizations and medications - and not always correctly. But even travelers who seek out professionals in the field do not always walk away with necessary information, either because it was not given or was given in a way that the traveler did not fully comprehend. For example, surveys continue to show that travelers do not use malaria medication correctly, do not follow food and water precautions and, when they come home ill, fail to tell their physicians of recent trips. Nor do most physicians ask patients, "Did you travel recently?" When the answer is "no," this process takes less than five seconds. When the answer is "yes," it can cut in half the length of the workup and may be lifesaving.

Here are some of the recommendations heard in an open forum on improving the quality and delivery of travel medicine health care:

• More time spent in conversation with the traveler.
• Handouts. These have to be simple, to the point, and relatively short. Most travelers will not read long, detailed articles. Even fewer travelers buy books on travelers' health.
• Label handouts "Read at Your Destination" and "Read on Returning Home."
• Phone calls to travelers on their return home.
• Mailings to patients several weeks after the initial visit addressed to their overseas address for long-term travelers and home address for short-term travelers.
• Stickers to attach to passports and immunizations cards.
• More lectures and publications for primary health care practitioners on travel medicine.
• Travel health-related articles for magazines found aboard airlines. (Most such magazines now have articles on the prevention of deep vein thrombosis.)
• Posters for emergency rooms and doctors' offices to remind both patients and staff to discuss recent travel.

The facts that the conference took place in Southeast Asia and that more than half of the faculty resides in this part of the world added relevancy to the meeting. This is the "epicenter" of SARS and H5N1. One speaker related how 1.5 million poultry were destroyed in a matter of three days in Hong Kong and how this possibly prevented a worldwide pandemic. Another speaker discussed the difficulties in producing effective vaccines and medications to counteract the H5NI virus. Present research, by necessity, targets the virus now circulating. Two factors that make H5N1 so ominous are its abilities to mutate frequently and to combine with human virus(es) during co-infection, creating a new virus that is quite different from the virus now in circulation.

Fortunately, while H5N1 possesses most of the prerequisites to start a major pandemic, it still lacks the ability to spread efficiently among humans and to sustain that ability.

Here is some other interesting information presented by speakers. (These opinions are those of the speakers, recognized experts in travel medicine.)

"No diversion" clause/Airline tickets. While chances are that you are familiar with the "Do Not Resuscitate" clauses for terminally ill patients in hospitals, you may not yet have heard of "No Diversion" clauses for critically ill airline passengers. Apparently, many such passengers/patients travel, usually to their country of origin to spend their final days there, and to die and be buried there. Such passengers are more likely to have serious medical events during flight, events that ordinarily dictate diversion of the aircraft for an immediate landing at an airport closer than the destination. Diversions add an element of risk, albeit a minor one, to the flight, are inconvenient to the other passengers aboard (delays can amount to six hours or more), and are extremely expensive for the airline. It may require dumping of fuel, landing costs, and delays. Costs are usually in the tens of thousands of dollars. At least one large Asian airline, when the airline is aware of such cases, requires that the patient or the patient's family sign a document stating that under no circumstances will the aircraft be diverted for a medical reason relating to this passenger.

Laos/Travel medicine. Laos is attracting an increasing number of visitors, with many venturing into remote parts of the country, exposing themselves to food-borne diseases rarely seen in the developed world. In the past, home cooking was the typical source of outbreaks, and outbreaks were small in scope. Today more people eat outside the home and 80% of such diseases occur from exposure outside the home. Raw or undercooked foods are popular and there have been large increases in the production of aquaculture foods. Sanitation, which has always been problematic, has not kept up with the expansion of the food industry, especially aquaculture food production. Laos is a high transmission area for trematode and nematode infections, in large part from eating raw or undercooked seafood. Diseases being reported with increased frequency in Laos and the symptoms associated with them include:

• Opistorchiasis. From ingestion of fresh water fish. Causes acute liver disease and may lead to liver cancer.
• Paragonimosis. From ingestion of crabs. Causes chronic coughs, bloody sputum, and secondary bacterial pneumonias.
• Angiostrongyloidosis and Gnathostomosis. From ingestion of crustacean, fishes, frogs, snakes, and snails. Causes eosinophilic meningitis.

Traffic-related mishaps account for the majority of morbidity and mortality among travelers in Laos, as in most developing countries. Traffic is "unruled" and increasing rapidly, and safety measures are not keeping up. Especially at risk in Laos are motorbike users and pedestrians. (WHO estimates that worldwide 1.2 million people die and 50 million are injured in traffic-related accidents.)

Dengue fever. Dengue may be the most important emerging disease among travelers to Southeast Asia and has become the most common arboviral disease in the tropics and subtropics, areas increasingly popular with tourists. In some studies, dengue is the second most common cause of hospitalization (after malaria) among travelers returning from the tropics. In another recent report the disease was the most frequent cause of fever in travelers returning from Asia.

Developing countries: Arrival of large number of refugees, immigrants, and migrants. Health care issues and other problems caused by the presence of large numbers of refugees, migrants, and immigrants from poorer nations are not limited to the so-called wealthy nations of the developed world. In Thailand, for example, relative economic and social stability has become a significant `pull' factor, attracting many individuals from nearby countries. This phenomenon tends to occur anytime one country raises its standard of living more rapidly than that of its neighbors. However, by most international standards, Thailand remains a developing country with considerable illiteracy, poverty, high rates of many diseases and a high infant mortality rate, for example. Presently more than 1.5 million "irregular" visitors (the exact number is unknown) from poorer neighboring countries reside in Thailand. More than 80% of the "irregulars" are believed to originate from Myanmar. These visitors bring new health-related issues, stretch resources and cause friction, especially in a country barely able to cope with its own health-related problems. Thailand's health system is one of the most advanced in the region and is implemented through a network of primary health care centers, community and general hospitals across 795 districts in Thailand's 63 provinces.

Rabies/Routine pre-exposure vaccinations/School children/Thailand. Rabies remains a significant public health problem in developing countries where post-exposure prophylaxis is costly and canine rabies is endemic. Children are the most vulnerable population and represent the majority of rabies deaths worldwide. In school-aged children in Thailand, a pre-exposure immunization regimen of three intradermal doses of purified chick embryo cell vaccine led to adequate immune responses. After primary vaccination all subjects developed rabies virus neutralizing antibodies and demonstrated a rapid increase in RVNA titer after two stimulated post-exposure booster immunizations one year after the primary vaccination series. The authors conclude that implementation of pre-exposure immunization could save the lives of many children in rabies-endemic areas.

Karl is the editor of this Newsletter. In addition, he writes frequently about travel medicine for both professionals and the public.