Gippy Tummy or Gyppy Tummy (traveler’s diarrhea)

Entry in progress—B.P.
 
Wikipedia: Traveler’s diarrhea
Traveler’s diarrhea (TD) is a stomach and intestinal infection. TD is defined as the passage of unformed stool (one or more by some definitions, three or more by others) while traveling. It may be accompanied by abdominal cramps, nausea, fever, and bloating. Occasionally bloody diarrhea may occur. Most travelers recover within four days with little or no treatment.[3] About 10% of people may have symptoms for a week.  (...)  It has colloquially been known by a number of names, including “Montezuma’s revenge” and “Delhi belly”.
(...)
Society and culture
Montezuma’s revenge (var. Moctezuma’s revenge) is a colloquial term for traveler’s diarrhea contracted in Mexico. The name refers to Moctezuma II (1466–1520), the Tlatoani (ruler) of the Aztec civilization who was overthrown by the Spanish conquistador Hernán Cortés in the early 16th century, thereby bringing large portions of what is now Mexico and Central America under the rule of the Spanish crown.
 
(Oxford English Dictionary)
gippy tummy  n. diarrhœa suffered by visitors to hot countries.
1943   A. Moorehead Year of Battle i. 22   Few set foot in Egypt without contracting ‘Gyppy Tummy’ which is a mild stomach disorder lasting usually a couple of days. It recurs at irregular intervals and it makes you feel terrible.
1948   E. Partridge et al. Dict. Forces’ Slang 89   Gyppy tummy, a sharp griping pain, accompanied by diarrhœa, very common in Egypt.