Which pathogen is the most common cause of traveler's diarrhea?

Escherichia coli is the most common cause of traveler's diarrhea, especially a specific strain known as enterotoxigenic E. coli (ETEC). This pathogen is prevalent in many developing countries and is frequently associated with the consumption of contaminated food and water during travel. ETEC produces toxins that lead to watery diarrhea, abdominal cramps, and nausea, which makes it a frequent concern for individuals visiting areas where sanitation practices may not be stringent.

While other pathogens can cause diarrhea during travel, such as Shigella, Vibrio cholerae, and Salmonella, they are less commonly responsible compared to E. coli. Shigella typically leads to more severe dysentery with bloody diarrhea, Vibrio cholerae primarily causes cholera with massive watery diarrhea in specific endemic areas, and Salmonella often involves more severe gastrointestinal symptoms but is not the dominant cause of travel-related illness. Therefore, E. coli stands out as the leading pathogen associated with traveler's diarrhea.