The diarrhea of travelers: incidence in foreign students in the United States.

To ascertain whether foreign visitors to the United States experience the diarrhea of travelers, 215 foreign students matriculating at the University of California, Los Angeles, were interviewed. The attack rate of diarrhea was 14.0 per cent during the first month after arrival in the United States. In a comparison group of 238 U.S. students, the attack rate of diarrhea in one month was 8.4 per cent. The difference in attack rate was not statistically significant. The diarrheal episodes reported by the foreign students were less abrupt in onset, less severe and of longer duration than the usual diarrhea of travelers. The typical severe explosive diarrhea of short duration usually described as "diarrhea of travelers" was not encountered among the foreign students in this study. The occurrence of diarrhea was not associated with the age, sex or race of the students, with the location of eating places, with the geographic area from which the foreign students came or with any characteristics of the trip to the United States. In the group of U.S. students there was an increased incidence of diarrhea among students who came from outside California to Los Angeles.