What pathogen is commonly responsible for traveler's diarrhea?

Traveler's diarrhea is primarily caused by enterotoxigenic Escherichia coli (ETEC), which is a common pathogen encountered in travelers visiting areas with poor sanitation. ETEC produces toxins that can lead to watery diarrhea, and it is often transmitted through contaminated food and water. The hallmark of ETEC infection is the sudden onset of profuse, watery diarrhea, often accompanied by abdominal cramps, but typically without fever or significant vomiting.

Other pathogens listed, such as Vibrio species, E. coli O157:H7, and Staphylococcus aureus, can cause gastrointestinal symptoms, but they are less commonly associated with the typical presentation of traveler's diarrhea. Vibrio parahaemolyticus is usually associated with seafood and may lead to diarrhea, but it is not the primary cause of traveler's diarrhea. E. coli O157:H7 is typically linked to more severe disease, including bloody diarrhea and hemolytic uremic syndrome, which is not characteristic of the traveler's diarrhea caused by ETEC. Staphylococcus aureus is more commonly associated with food poisoning rather than traveler's diarrhea associated with contaminated food or water during travel. Thus, ETEC is recognized as the classic cause of this condition among travelers.