Etiology Travelers diarrhea commonly results from an infection caused by one of a number of different pathogens. Enterotoxigenic E. coli is the most common etiology. Vibrio species, such as parahemolyticus , can cause diarrhea in persons who eat raw or incompletely cooked seafood. Protozoa, such as Giardia lamblia , Entameba histolytica and Cryptosporidium are less frequent causes for diarrhea. Clinical Presentation Symptoms vary according to the underlying etiology, but affected travelers typically have frequent daily stools lasting several days.
Symptoms can range from only a few episodes of diarrhea to multiple profuse, watery stools.
High fever, significant abdominal pain, and bloody stools are hallmarks of a more serious diarrhea, which should cause the traveler to seek medical attention immediately. In most cases, the traveler should carry along an antibiotic to take should diarrhea develop. Treatment with a fluoroquinolone antibiotic for 3 days is safe and effective in adults with mild to moderate symptoms. A one-day course is less effective, but sometimes adequate. An alternative to fluoroquinolones is azithromycin, which can be used if the bacteria seem to exhibit fluoroquinolone resistance.