Travel extending beyond six months is associated with health risks not usually encountered among short-term travellers, new data indicate.
Issues of most concern for long-term travellers are psychological problems and diseases caused by parasites.
"Few studies have compared the types and causes of illness in travellers on the basis of duration of travel," Dr Lin H. Chen, from the Mount Auburn Hospital in Cambridge, Massachusetts, and members of the GeoSentinel Surveillance Network note the journal Emerging Infectious Diseases.
Their study used data from ill travellers who visited GeoSentinel sites -- clinics on six continents that specialise in travel medicine - from 1996 through 2008. Included in the analysis were 4 039 persons who travelled for more than six months, and 24 807 who travelled for less than one month.
Long term travellers more affected
Long-term travellers were significantly more likely than short-term travellers to have a variety of ailments including persistent fatigue, chronic diarrhoea, malaria and post-infectious irritable bowel syndrome.
They were also much more likely to come down with leishmaniasis, a disease caused by a parasite transmitted by a tiny sandfly that can lead to severe scarring, and the parasitic worm disease schistosomiasis.
"Many common infections seen in long-term travellers are preventable by vaccines, vector avoidance, food/water precautions, and avoidance of soil and fresh water," the researchers note.
Psychological diagnoses that were significantly more common in long-term travellers included depression, stress, and fatigue.
"The increased number of missionary/volunteer/research/aid workers with stress was most significant," the investigators report.
Chen and colleagues point out that 70% of the long-term travellers in their study made pre-travel visits to health care providers.
"Opportunities exist to educate, vaccinate, provide malaria chemoprophylaxis, and prepare these travellers for possible break-through infection," they conclude. – (Reuters Health, October 2009)
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