Which E. coli subtype causes small bowel traveler's diarrhea?

Enterotoxigenic E. coli (ETEC) is the subtype responsible for causing small bowel traveler's diarrhea. This strain produces enterotoxins that stimulate the intestinal lining, leading to increased secretion of fluids and electrolytes, which results in watery diarrhea. ETEC is commonly associated with unclean food and water sources in areas where hygiene practices may not be optimal, making it a frequent concern for travelers.

In contrast, other subtypes of E. coli are linked to different disease mechanisms and clinical presentations. Enteroinvasive E. coli (EIEC) invades the epithelial cells of the intestine, causing dysentery-like symptoms. Enteropathogenic E. coli (EPEC) is known for its ability to adhere to and destroy microvilli in the intestines, leading to watery diarrhea more commonly in infants. Enterohemorrhagic E. coli (EHEC), particularly the O157:H7 strain, can cause severe, bloody diarrhea and is associated with outbreaks linked to undercooked beef and contaminated vegetables, along with the risk of hemolytic uremic syndrome.

Understanding the specific characteristics of ETEC is crucial, especially in the context of travel medicine and public health, as preventative measures can be taken to