Characterization of vancomycin-resistant and vancomycin-susceptible Enterococcus faecium isolates from humans, chickens and pigs by RiboPrinting and pulsed-field gel electrophoresis

Forty-eight vancomycin-resistant and 35 vancomycin-sensitive Danish Enteroc occus faecium isolates obtained from pigs, chickens and humans, as well as the human vanA reference isolate BM4147, were characterized by EcoRI RiboPr inting and Smal pulsed-field gel electrophoresis. RiboPrinting of the 84 is olates yielded 40 types whereas PFGE-typing yielded 57 types discriminated by differences in more than three bands. By molecular typing, both clonal s pread of E. faecium as well as horizontal transmission of Tn1546 between an imals and humans was supported. Furthermore, it was found that the populati on of E. faecium spreads freely between the animal and human reservoir.