Geographic variation of the etiology of travelers\u27 diarrhea

Introduction. Traveler\u27s Diarrhea is an important public health program in travelers from industrialized nations to the developing world with a prevalence rate of between 13 and 60%. Although studies are found on the etiology of traveler\u27s diarrhea, these studies have not described the etiology over different regions of the world. The objective of this study was to identify the frequency of specific etiology of traveler\u27s diarrhea by geographic area of the world. In addition to this, it was also examined whether there are any regional differences in the isolation rate of ETEC and conventional pathogens and variation, if any, in frequency of these pathogens in different regions over time. Material and methods. This is a systematic review of the studies on the etiology of traveler\u27s diarrhea by geographic regions. The search databases used were Medline Pubmed and Medline Ovid and key words used for the search were Etiology of traveler\u27s diarrhea, travelers\u27 diarrhea and acute diarrhea of travelers. The articles were selected according to the inclusion and exclusion criteria and relevant data was extracted which was statistically analyzed. Results. Out of 110 studies from 1970 to 2004, 52 studies were included and 58 were excluded from the review. All the 52 studies were grouped according to the geographic regions of interest. Latin America (25 studies), Asia (7 studies), Africa (9 studies), and others/Mixed (11 studies), were the 4 major groups of regions studied. The overall most common pathogen was ETEC (29.10%) in this study and other common pathogens were EAEC (14.42%), norovirus (10.95%), EPEC (6%) and rotavirus (5.23%). ETEC and Shigella show a decreasing trend in Latin America & Caribbean but increasing trend in Asia. Conclusion. ETEC is the single most common cause of travelers\u27 diarrhea in the world. Potent vaccines against ETEC are required to prevent travelers\u27 diarrhea and thus reduce the attack rate. Also, PCR based studies are required to identify the causes of pathogen negative diarrhea