Surveillance was conducted during February and March 1991 in the pediatric emergency department of Cayetano Heredia Hospital, Lima, Peru, to contrast the characteristics of children with epidemic cholera with those of children with non-cholera-associated diarrhea. Among 626 patients 14 years of age or younger, Vibrio cholerae O1 was isolated from stool specimens of 310 patients (49%), more commonly from children older than 24 months of age (66%; p <0.0001) than from younger children. Cholera was clinically characterized by a more sudden onset; watery diarrhea; and associated abdominal pain, muscle cramps, and vomiting, which led to more severe dehydration and hospitalization more often than in noncholera cases. Only one patient with cholera died, for a case-fatality rate of 3.2 deaths per 1000 persons. Nonpotable water and uncooked foods were identified as probable vehicles for V. cholerae. The frequency of diarrhea among relatives of patients with cholera suggested intrafamily transmission. This study of epidemic cholera describes the clinical features and the risk factors for acquisition of the infection, and points out the low case-fatality rate with prompt and appropriate treatment. (J PEDIATR 1995;126:882-6). © 1995 Mosby, Inc. All rights reserved.