Diagnóstico bacteriológico del Cólera. Actividades del Laboratorio Nacional de Referencia

Abstract

Following WHO recommendations, a country at risk for cholera should establish a National Reference Laboratory; during the recent outbreak of cholera, the Colombian INS assumed the responsibility of training health personnel, supplying materials and monitoring quality assurance. All state laboratories participated in the training course, During 23 months of the outbreak (Frebruary 1991- December 1992) we isolated and identified 1412 strains of Vibrio cholera O1 (bt growth in TCBS agar, oxidase, string test and agglutination) from 5032 samples received from 32 out of 33 states an have confirmed all the 1919 strains sent by 22 regional laboratories. Of the 3331 strains, 3302 (99.13%) were subtype Inaba and 29 (0.87%) subtype Ogawa. Twenty strains have been further characterized by their biochemical and immunological properties. In five of them we also did the differential tests for biotypification and tested the toxin production. The biochemical, biotyping and immunological patterns characterize the strains as V. cholerae O1 biotype El Tor, toxin producers. All the 138 strains tested are totally susceptible to tetracycline. Our previous Clinical Bacteriology Laboratory Network program allowed us to assume the role of the National Reference Laboratory in cholera.