Gert van der Hoek
In Memoriam - Editor, Senior Moderator
Clinical Infectious Diseases Advance Access published December 14, 2012
1Extended-Spectrum β-Lactamase?Producing
Escherichia coli From Retail Chicken Meat and
Humans: Comparison of Strains, Plasmids,
Resistance Genes, and Virulence Factors
Jan A. J. W. Kluytmans, Ilse T. M. A. Overdevest, Ina Willemsen, Marjolein F. Q. Kluytmans-van den Bergh, Kim van der Zwaluw, Max Heck, Martine Rijnsburger, Christina M. J. E. Vandenbroucke-Grauls, Paul H. M. Savelkoul, Brian D. Johnston, David Gordon, and James R. Johnson
Background. The worldwide prevalence of extended-spectrum β-lactamase (ESBL)?producing Enterobacteriaceae is increasing rapidly both in hospitals and in the community. A connection between ESBL-producing bacteria
in food animals, retail meat, and humans has been suggested. We previously reported on the genetic composition
of a collection of ESBL-producing Escherichia coli (ESBL-EC) from chicken meat and humans from a restricted
geographic area. Now, we have extended the analysis with plasmid replicons, virulence factors, and highly discriminatory genomic profiling methods.
Methods. One hundred forty-five ESBL-EC isolates from retail chicken meat, human rectal carriers, and
blood cultures were analyzed using multilocus sequence typing, phylotyping, ESBL genes, plasmid replicons, virulence genes, amplified fragment length polymorphism (AFLP), and pulsed-field gel electrophoresis (PFGE).
Results. Three source groups overlapped substantially when their genetic composition was compared. A combined analysis using all variables yielded the highest resolution (Wilks lambda [Λ]: 0.08). Still, a prediction model
based on the combined data classified 40% of the human isolates as chicken meat isolates. AFLP and PFGE
showed that the isolates from humans and chicken meat could not be segregated and identified 1 perfect match
between humans and chicken meat.
Conclusions. We found significant genetic similarities among ESBL-EC isolates from chicken meat and
humans according to mobile resistance elements, virulence genes, and genomic backbone. Therefore, chicken
meat is a likely contributor to the recent emergence of ESBL-EC in human infections in the study region. This
raises serious food safety questions regarding the abundant presence of ESBL-EC in chicken meat.
CID Oxford Journals
1Extended-Spectrum β-Lactamase?Producing
Escherichia coli From Retail Chicken Meat and
Humans: Comparison of Strains, Plasmids,
Resistance Genes, and Virulence Factors
Jan A. J. W. Kluytmans, Ilse T. M. A. Overdevest, Ina Willemsen, Marjolein F. Q. Kluytmans-van den Bergh, Kim van der Zwaluw, Max Heck, Martine Rijnsburger, Christina M. J. E. Vandenbroucke-Grauls, Paul H. M. Savelkoul, Brian D. Johnston, David Gordon, and James R. Johnson
Background. The worldwide prevalence of extended-spectrum β-lactamase (ESBL)?producing Enterobacteriaceae is increasing rapidly both in hospitals and in the community. A connection between ESBL-producing bacteria
in food animals, retail meat, and humans has been suggested. We previously reported on the genetic composition
of a collection of ESBL-producing Escherichia coli (ESBL-EC) from chicken meat and humans from a restricted
geographic area. Now, we have extended the analysis with plasmid replicons, virulence factors, and highly discriminatory genomic profiling methods.
Methods. One hundred forty-five ESBL-EC isolates from retail chicken meat, human rectal carriers, and
blood cultures were analyzed using multilocus sequence typing, phylotyping, ESBL genes, plasmid replicons, virulence genes, amplified fragment length polymorphism (AFLP), and pulsed-field gel electrophoresis (PFGE).
Results. Three source groups overlapped substantially when their genetic composition was compared. A combined analysis using all variables yielded the highest resolution (Wilks lambda [Λ]: 0.08). Still, a prediction model
based on the combined data classified 40% of the human isolates as chicken meat isolates. AFLP and PFGE
showed that the isolates from humans and chicken meat could not be segregated and identified 1 perfect match
between humans and chicken meat.
Conclusions. We found significant genetic similarities among ESBL-EC isolates from chicken meat and
humans according to mobile resistance elements, virulence genes, and genomic backbone. Therefore, chicken
meat is a likely contributor to the recent emergence of ESBL-EC in human infections in the study region. This
raises serious food safety questions regarding the abundant presence of ESBL-EC in chicken meat.
CID Oxford Journals