Etiology and epidemiology of travelers' diarrhea in Asia

Travelers' diarrhea in Asia has been studied among Peace Corps volunteers in Thailand, Japanese travelers, foreign residents in Bangladesh, guests in hotels, and members of various tour groups. Rates of diarrheal attack of greater than 50% during four- to six-week sojourns were reported for these groups. Among travelers with diarrhea, the most commonly isolated pathogen was enterotoxigenic Escherichia coli (20%-34%), followed by Salmonella (11%-15%), Shigella (4%-7%), Campylobacter (2%-5%), and Vibrio parahaemolyticus (1%-13%). In 9%-22% of diarrheal episodes, multiple pathogens were recovered. Among Japanese travelers, Salmonella was more commonly acquired in the Far East; Shigella and Campylobacter, in the Indian subcontinent; and V. parahaemolyticus, in Southeast Asia. Aeromonas hydrophila and Plesiomonas shigelloides were commonly isolated from ill travelers in Thailand but less frequently from other travelers. Protozoa and Vibrio species other than V. parahaemolyticus were isolated in less than 5% of episodes.