Characterization of vanA-type Enterococcus faecium isolates from urban and hospital wastewater and pigs.
OBJECTIVE
In this study we analysed urban, hospital wastewater and pig faeces samples to investigate the presence of vancomycin-resistant Enterococcus faecium strains (VREF) and to determine potential links among the strains originating from the above sources and VREF strains causing clinical infections.


RESULTS
Urban, hospital wastewater and pig faeces exhibited high VREF prevalence of 52%, 87% and 85%, respectively. Pulsed field gel electrophoresis (PFGE) clustering of VREF genotypes as well as discriminant analysis of antibiotic resistance patterns of VREF strains revealed their source specificity while strains isolated from hospitalized humans were genetically distinct.


CONCLUSIONS
PFGE genotypes and antimicrobial resistance patterns in VREF isolates are distinguishable by each sample origin. The observed high genetic diversity of VREF suggests horizontal transfer of genetic elements among VREF. Phenotypic and genotypic data indicate that VREF isolates of hospital-treated wastewater might pass to the urban wastewater system.


CONCLUSIONS
This study provides information to understand the origin and the mechanism of circulation of vancomycin resistance in food animals and wastewater treatment plants for minimizing the risk of transmission of VRE in human population.
Kotzamanidis
C
C
Department of Genetics, Development and Molecular Biology, School of Biology, Aristotle University of Thessaloniki, Thessaloniki, Greece.
Zdragas
A
A
Kourelis
A
A
Moraitou
E
E
Papa
A
A
Yiantzi
V
V
Pantelidou
C
C
Yiangou
M
M