Cluster analysis of Salmonella Enteritidis populations isolated in various regions of Siberia and the Far East

Abstract

Objerctive. Salmonella infection is the most common intestinal infection in the world. The goal of this study was to study the population structure of Salmonella Enteritidis, isolated in the Far East and Siberia from various environmental sources, using modern methods of cluster analysis. Methods. 345 S. Enteritidis strains isolated from patients and from food in 1989-2018 were studied with sporadic and flare morbidity of the population belonging to the ten major plasmid types. For the classification multidimensional analysis of the results containing genetic (composition of plasmids in the strains) and phenotypic (antibiogram) data, the cluster analysis method was used. Results. To determine the number of clusters, an independent simulation was performed with their estimated number (from 2 to 15). The data of stratification analysis revealed 9 clearly distinguishable clusters with a large number of impurities from other clusters. The detected clusters were rather clearly defined by the corresponding plasmid types of the pathogen. Conclusions. No differences were found in the strains isolated in the western and eastern regions of the Russian Federation. The effectiveness of using plasmid analysis as a method for determining pathogen populations has been confirmed.