Epidemiology of Enterococcus faecium isolates sampled from different sources in Romania using MLST technique and eBURST algorithm

Abstract

Enterococcus faecium is emerging as an important cause of multidrug resistance and hospital acquired infections, special attention being paid to the vancomycin resistant species. Therefore, the characterization of pathogenic strains/isolates plays an important role in the epidemiology of infectious diseases. The enterococcal rate was determined from wastewaters in Cluj-Napoca area. As presence of E. faecium was detected, a number of isolates from wastewater, birds and humans were epidemiologically analyzed according to the MLST website. Comparisons were performed against a collection of available isolates, with multiple origins, contained in the MLST database. Out of the Enterococcus isolates collected from wastewater, 11 were identified as E. faecalis (40.74%); 8 as E. casseliflavus (29.62%); 5 as E. faecium (18.50%); 2 as E. gallinarum (7.40%) and one isolate as E. durans. Based on the MLST data and using the eBURST algorithm, the isolates of E. faecium sampled from Romania were split in three groups: one group comprised isolates from human hosts and wastewater (Cj316, 106/6, Cj197, Cj22, 129/6, Cj117, Cj24, 284/7, and 43/7), while the second (G9, G10-2, G7, G3-2, and G9-1) and the third group (G8, G6, and 40/7) originated from bird hosts. The rest of the isolates were not joined in a particular group, assuming the lack of a phylogenetic bond between these isolates. The obtained data suggested the existence of at least two phylogenetic lines of E. faecium in Romania: a line that had mainly human host prevalence, while in the other line the animal hosts dominated.