Which condition is commonly known as Montezuma's revenge?

Montezuma's revenge refers specifically to traveler's diarrhea, which is a common gastrointestinal issue faced by travelers, particularly to areas with different sanitary practices or unfamiliar food and water sources. This condition is usually caused by ingesting contaminated food or water, often containing pathogens such as bacteria, viruses, or parasites. Symptoms typically include diarrhea, abdominal cramps, nausea, and sometimes fever. The term itself is colloquially used to describe the unpleasant effects of gastrointestinal upset that can occur when adapting to different health standards in a foreign location.

In contrast, chronic fatigue syndrome is characterized by persistent fatigue not alleviated by rest and not directly associated with food or water consumption. Severe food poisoning can cause symptoms similar to traveler's diarrhea but does not specifically align with the cultural context or the nature of the illness acquired while traveling. Influenza-like illness involves respiratory symptoms and is viral rather than gastrointestinal in nature, making it unrelated to the context of Montezuma's revenge. Thus, traveler's diarrhea is the most accurate condition reflecting the symptoms and circumstances associated with this colloquial term.