Travelers' diarrhea. Epidemiology, prevention, and self-treatment.

Risk factors for travelers' diarrhea include adventurous behavior, consumption of unclean water or food, and special hosts like those taking long acting H2 blockers. Approaches to prevention include education about risk factors, which often fails to lead to modification of risky behavior, and chemoprophylaxis with bismuth subsalicylate-containing compounds or antimicrobial agents. Chemoprophylaxis is generally discouraged except in special circumstances and in high-risk hosts. Self-treatment of travelers' diarrhea is successful in limiting the course of diarrhea and minimizing losses of vacation and business time. Current therapeutic options, in order of increasing effectiveness, include attapulgite, BSS-containing compounds, loperamide, antimicrobial agents such as the fluoroquinolones, and the combination of loperamide and an antimicrobial agent. Under study are a nonabsorbed antimicrobial agent, rifaximin, and a novel calmodulin inhibitor, zaldaride. Development and evaluation of vaccines against enterotoxigenic Escherichia coli and Shigella are proceeding apace but are not yet available for routine use.