Travelers' Diarrhea in Mexico: A Prospective Study of Physicians and Family Members Attending a Congress

We conducted a prospective study of travelers' diarrhea on 73 physicians and 48 family members attending a medical congress in Mexico City, in October, 1974. Fecal and blood specimens were collected before, during and after their visit and examined for enteric bacterial pathogens, viruses and parasites. In 59 (49 per cent) participants travelers' diarrhea developed. Median duration of illness was five days. Onset occurred a median of six days after arrival. An etiologic agent was found in 63 per cent of ill participants. Enterotoxigenic Escherichia coli of different, non-“enteropathogenic” serotypes was the most common cause; other responsible pathogens included salmonellae, invasive Esch. coli., shigellae, Vibrio parahaemolyticus, Giardia lamblia and the human reovirus-like agent. Consumption of salads containing raw vegetables was associated with enterotoxigenic Esch. coli infection (P = 0.014). Travelers' diarrhea in Mexico is a syndrome caused by a variety of pathogens, the most common of which is enterotoxigenic Esch. coli. (N Engl J Med 294:1299–1305, 1976) AMERICANS traveling in foreign countries often experience “travelers' diarrhea” shortly after arrival. This illness can be mild and short-lived but is sometimes prolonged and incapacitating. In travelers to Mexico the illness which is frequently called “turista” or ”Montezuma's revenge,” has an attack rate of 24 to 50 per cent.¹²³The cause of “turista” was unknown until a recent study demonstrated that strains of Escherichia coli that produce heat-labile enterotoxin play an important part.³The vehicles responsible for this illness have not been identified, and thus preventive measures have been difficult to define. To characterize more clearly the clinical, epidemiologic and.