Epidemic cholera in Trujillo, Peru 1992: utility of a clinical case definition and shift in Vibrio cholerae O1 serotype.

Epidemic cholera continues in Peru. Since 1991, cholera surveillance in Peru has been based mainly on clinical recognition. To determine the proportion of reported cholera patients who actually have cholera and to evaluate the clinical case definition used in surveillance, we cultured rectal swabs from patients presenting with acute diarrhea in March 1992 in Trujillo, Peru. Of 197 patients meeting the clinical case definition, 174 (88%) had confirmed Vibrio cholerae O1 infection. In this epidemic setting, watery diarrhea of sudden onset in a person of any age presenting for treatment is highly predictive of cholera. Of note, 90% of the current V. cholerae O1 El Tor isolates were of serotype Ogawa, while a year earlier, all were of serotype Inaba.