Dispersion of Multidrug-Resistant Enterococcus faecium Isolates Belonging to Major Clonal Complexes in Different Portuguese Settings

Abstract

The population structure of 56 Enterococcus faecium isolates selected from a collection of enterococci from humans, animals, and the environment in Portugal (1997 to 2007) was analyzed by multilocus sequence typing. We identified 41 sequence types clustering into CC17, CC5, CC9, CC22 and CC94, all clonal lineages comprising isolates from different hosts. Our findings highlight the role of community-associated hosts as reservoirs of enterococci able to cause human infections.

Genetic Variability of Vancomycin-Resistant Enterococcus faecium and Enterococcus faecalis Isolates from Humans, Chickens, and Pigs in Malaysia

“…The clone is infrequently reported as a clinical strain and has been described as a chicken strain by Freitas et al (55). However, this ST was not found in the chickens in the present study.…”

“…The strains of ST29 and ST57 that were isolated from chickens in this study were also reported to be isolated from people in the community and from pigs in Brazil, France, Australia, and Belgium. ST29 and ST57 belong to CC9 that has been identified as a global chicken lineage complex (55).…”

Human and Swine Hosts Share Vancomycin-Resistant Enterococcus faecium CC17 and CC5 and Enterococcus faecalis CC2 Clonal Clusters Harboring Tn 1546 on Indistinguishable Plasmids

“…Besides dispersal of animals in global markets, the selective pressure exerted by antibiotics (e.g., tetracyclines and ␤-lactams) or metals (e.g., copper) heavily used in veterinary medicine and husbandry may have contributed to the maintenance of VRE among swine farms and facilitated the horizontal transfer of conjugative plasmids to other enterococcal hosts (or other Grampositive species serving as intermediates in the processes of horizontal gene transfer). Similarly to that described for E. faecium CC5, widespread clones of the predominant human enterococcal lineage E. faecium CC17 or E. faecalis CC2 have been recovered from companion and farm animals (4,9,13,14).…”

“…ST132 is an SLV of ST18, a predominant clone of the CC17 polyclonal subcluster. Although ST132 is not a predominant CC17 clone, isolates belonging to the ST have been recovered from unrelated patients hospitalized in Portugal and Tanzania, and it has been associated with a nosocomial outbreak described in Spain during an 18-month period, suggesting potential transmissibility (14,39,43,53; http://efaecium.mlst.net).…”

“…Strains from human-adapted clonal complexes (CCs) causing most enterococcal infections may eventually be recovered from farm and companion animals (e.g., E. faecium clonal complex 17 [CC17] and E. faecalis CC2), and strains from CCs commonly found among animals have also been isolated from humans (E. faecium CC5, E. faecalis sequence type 16 [ST16], or E. faecalis CC21) (4,9,13,14,28,53). Documented cases of animal-human VRE transmission frequently involve healthy humans in close interaction (farming or petting) with animals, but most of these studies do not provide molecular characterization of either clones or their subcellular genetic elements (1,3,10,17,26,28,31,33), despite the comprehensive epidemiological studies of Tn1546 (vanA) and Tn5382 (vanB) (8,24,38,52,54).…”