Ribotyping of Salmonella Enteritidis strains reveals the spread of a single genotype in the Brazilian city of Ribeirão Preto

Abstract

Background: The approach generally employed in leading laboratories worldwide to identify strains of Salmonella is to detect epidemiological markers by serotyping and molecular techniques. These molecular methods are important in sanitary surveillance and lead to the source of infection. Objectives: The aim of the present study is to characterize Salmonella Enteritidis strains by ribotyping. Material and methods: Thirty-eight strains of S. Enteritidis were isolated from in patients at the university hospital of Universidade de São Paulo, Ribeirão Preto, SP, Brazil, between 1996 and 1998. These strains were isolated from stools (31 samples), blood (4 samples) and other body fluids (3 samples), using routine bacteriological methods, and were serotyped and ribotyped. Results: The 38 strains of serotype S. Enteritidis were shown by the ribotyping to belong to two ribotypes: A (94.7% of the samples) and B (5.3%). Discussion and conclusion: These results suggest that the majority of patients (94.7%) were infected by the same strain. This strain could be endemic in the Ribeirão Preto community, or these patients may have been exposed to a common source of infection.