Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

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Characteristics of Cefotaxime-Resistant Escherichia coli from Wild Birds in The Netherlands
Veldman, K.T. ; Tulden, P. ; Kant, A. ; Testerink, J.J. ; Mevius, D.J. - \ 2013
Applied and Environmental Microbiology 79 (2013)24. - ISSN 0099-2240 - p. 7556 - 7561.
spectrum-beta-lactamase - extended-spectrum - antibiotic-resistance - natural reserve - ctx-m - salmonella - plasmids - gulls - enterobacteriaceae - environments
Cloacal swabs from carcasses of Dutch wild birds obtained in 2010 and 2011 were selectively cultured on media with cefotaxime to screen for the presence of extended-spectrum beta-lactamase (ESBL)/AmpC-producing Escherichia coli. Subsequently, all cefotaxime-resistant E. coli isolates were tested by broth microdilution and microarray. The presence of ESBL/AmpC and coexisting plasmid-mediated quinolone resistance (PMQR) genes was confirmed by PCR and sequencing. To determine the size of plasmids and the location of ESBL and PMQR genes, S1 pulsed-field gel electrophoresis (PFGE) was performed on transformants, followed by Southern blot hybridization. The study included 414 cloacal swabs originating from 55 different bird species. Cefotaxime-resistant E. coli isolates were identified in 65 birds (15.7%) from 21 different species. In all, 65 cefotaxime-resistant E. coli ESBL/AmpC genes were detected, mainly comprising variants of bla(CTX-M) and bla(CMY-2). Furthermore, PMQR genes [aac(6')-lb-cr, qnrB1, and qnrS1] coincided in seven cefotaxime-resistant E. coli isolates. Overall, replicon typing of the ESBL/AmpC-carrying plasmids demonstrated the predominant presence of IncI1 (n = 31) and variants of IncF (n = 18). Our results indicate a wide dissemination of ESBL and AmpC genes in wild birds from The Netherlands, especially among aquatic-associated species (waterfowl, gulls, and waders). The identified genes and plasmids reflect the genes found predominantly in livestock animals as well as in humans.
Comparative analysis of ESBL-positive Escherichia coli isolates from animals and humans from the UK, The Netherlands and Germany
Wu, G. ; Day, M.J. ; Mafura, T. ; Nunez-Garcia, J. ; Fenner, J.J. ; Sharma, M. ; Essen-Zandbergen, A. van; Rodriguez, I. ; Dierikx, C.M. ; Mevius, D.J. - \ 2013
PLoS One 8 (2013)9. - ISSN 1932-6203 - 10 p.
spectrum-beta-lactamase - calgary health region - extended-spectrum - ctx-m - companion animals - poultry products - public-health - resistance - strains - genes
The putative virulence and antimicrobial resistance gene contents of extended spectrum ß-lactamase (ESBL)-positive E. coli (n=629) isolated between 2005 and 2009 from humans, animals and animal food products in Germany, The Netherlands and the UK were compared using a microarray approach to test the suitability of this approach with regard to determining their similarities. A selection of isolates (n=313) were also analysed by multilocus sequence typing (MLST). Isolates harbouring blaCTX-M-group-1 dominated (66%, n=418) and originated from both animals and cases of human infections in all three countries; 23% (n=144) of all isolates contained both blaCTX-M-group-1 and blaOXA-1-like genes, predominantly from humans (n=127) and UK cattle (n=15). The antimicrobial resistance and virulence gene profiles of this collection of isolates were highly diverse. A substantial number of human isolates (32%, n=87) did not share more than 40% similarity (based on the Jaccard coefficient) with animal isolates. A further 43% of human isolates from the three countries (n=117) were at least 40% similar to each other and to five isolates from UK cattle and one each from Dutch chicken meat and a German dog; the members of this group usually harboured genes such as mph(A), mrx, aac(6’)-Ib, catB3, blaOXA-1-like and blaCTX-M-group-1. forty-four per cent of the MLST-typed isolates in this group belonged to ST131 (n=18) and 22% to ST405 (n=9), all from humans. Among animal isolates subjected to MLST (n=258), only 1.2% (n=3) were more than 70% similar to human isolates in gene profiles and shared the same MLST clonal complex with the corresponding human isolates. The results suggest that minimising human-to-human transmission is essential to control the spread of ESBL-positive E. coli in humans.
Cross-sectional study on prevalence and molecular characteristics of plasmid mediated ESBL/AmpC-producing Escherichia coli isolated from veal calves at slaughter
Hordijk, J. ; Wagenaar, J.A. ; Kant, A. ; Essen-Zandbergen, A. van; Dierikx, C.M. ; Veldman, K. ; Wit, B. ; Mevius, D.J. - \ 2013
PLoS One 8 (2013)5. - ISSN 1932-6203
spectrum-beta-lactamase - food-producing animals - extended-spectrum - ctx-m - salmonella-enterica - fecal carriage - antimicrobial resistance - host-range - cattle - enterobacteriaceae
Objectives - The presence of ESBL/AmpC-producing E. coli in cattle has been reported previously, however information on veal calves is limited. This study describes the prevalence and molecular characteristics of E. coli with non-wild type susceptibility to cefotaxime in veal calves at slaughter. Methods - Faecal samples from 100 herds, 10 individual animals per herd, were screened for E. coli with non-wild type susceptibility for cefotaxime. Molecular characterization of ESBL/AmpC genes and plasmids was performed on one isolate per herd by microarray, PCR and sequence analysis. Results - 66% of the herds were positive for E. coli with non-wild type susceptibility for cefotaxime. Within-herd prevalence varied from zero to 90%. 83% of E. coli producing ESBL/AmpC carried blaCTX-M genes, of which blaCTX-M-1, blaCTX-M-14 and blaCTX-M-15 were most prevalent. The dominant plasmids were IncI1 and IncF-type plasmids. Conclusions - A relatively high prevalence of various blaCTX-M producing E. coli was found in veal calves at slaughter. The genes were mainly located on IncI1 and IncF plasmids.
The public health risks of enterobacterial isolates producing extended-spectrum Beta-lactamases (ESBL) or AmpC Beta-lactamases in food and food-producing animals: An EU perspective of epidemiology, analytical methods, risk factors and control options
Liebana, E. ; Carattoli, A. ; Coque, T.M. ; Hasman, H. ; Magiorakos, A.P. ; Mevius, D.J. ; Peixe, L. ; Schuepbach-Regula, G. ; Torneke, K. ; Torren-Edo, J. ; Torres, C. ; Threlfall, J. - \ 2013
Clinical infectious diseases 56 (2013)7. - ISSN 1058-4838 - p. 1030 - 1037.
escherichia-coli - salmonella-enterica - ctx-m - antimicrobial resistance - plasmids - poultry - strains - farms - spain - identification
blaESBL and blaAmpC in Enterobacteriaceae are spread by plasmid-mediated integrons, insertion sequences and transposons, some of which are homologous in bacteria from food-animals, foods and humans. These genes have been frequently identified in Escherichia coli and Salmonella from food-animals; the most common genes being blaCTX-M-1, blaCTX-M-14, and blaCMY-2. Identification of risk factors for their occurrence in food-animals is complex. As well as generic antimicrobial use, cephalosporin usage is an important risk factor for selection and spread of these genes. Extensive international trade of animals is a further risk factor. There are no data on the effectiveness of individual control options in reducing public health risks. A highly effective option would be to stop or restrict cephalosporin usage in food-animals. Decreasing total antimicrobial use is also of high priority. Implementation of measures to limit strain dissemination (increasing farm biosecurity, controls in animal trade, and other general post-harvest controls) are also important.
Detection and characterization of pCT-like plasmid vectors for blaCTX-M-14 in Escherichia coli isolates from humans, turkeys and cattle in England and Wales
Stokes, M.O. ; Cottel, J.L. ; Piddock, L.J. ; Wu, G. ; Wootton, M. ; Mevius, D.J. ; Randall, L.P. ; Teale, C.J. ; Fielder, M.D. ; Coldham, N.G. - \ 2012
Journal of Antimicrobial Chemotherapy 67 (2012)7. - ISSN 0305-7453 - p. 1639 - 1644.
spectrum-beta-lactamase - ctx-m - salmonella - ctx-m-14 - enterobacteriaceae - resistance - strains - france - gene - uk
Objectives - To detect and characterize Escherichia coli strains and pCT-like plasmids implicated in the dissemination of the CTX-M-14 gene in animals and humans, in England and Wales. Methods UK CTX-M-14-producing E. coli (n¿=¿70) from cattle (n¿=¿33), turkeys (n¿=¿9), sheep (n¿=¿2) and humans (n¿=¿26) were screened using multiplex PCR for the detection of a previously characterized plasmid, pCT. Isolates found to be carrying two or more pCT genetic markers were further analysed using PFGE. Their antimicrobial-resistance genes and virulence genes were also determined. These plasmids were transferred to Salmonella enterica serotype Typhimurium 26R and further examined for incompatibility type, genetic environment of the blaCTX-M-14 gene, size, restriction fragment length polymorphism (RFLP) and nikB sequence. Results - The 25 E. coli isolates carrying pCT genetic markers generated 19 different PFGE profiles, and 23 isolates had different virulence and antimicrobial-resistance gene patterns. One isolate from cattle was a verotoxigenic E. coli (‘VTEC’); the rest were commensal or extra-intestinal pathogenic E. coli. pCT-like plasmids with similar molecular characteristics (size, replicon type, RFLP pattern, pCT markers and genetic environment of the blaCTX-M-14 gene) were detected in 21/25 of the field isolates, which comprised those from cattle (n¿=¿9), turkeys (n¿=¿8) and humans (n¿=¿4). All pCT-like plasmids were conjugative, and most were IncK (n¿=¿21) and had the same local genetic environment flanking the blaCTX-M-14 gene (n¿=¿23). RFLP analysis demonstrated =75% similarity among most plasmids (n¿=¿22). Conclusions - pCT-like plasmids were common vectors for horizontal dissemination of 30% of the blaCTX-M-14 genes to
Virulence genes in bla (CTX-M) Escherichia Coli isolates from chickens and humans
Randall, L. ; Wu, G. ; Phillips, N. ; Coldham, N. ; Mevius, D.J. ; Teale, C. - \ 2012
Research in Veterinary Science 93 (2012)1. - ISSN 0034-5288 - p. 23 - 27.
beta-lactamase - ctx-m - diarrhea - resistance - strains - toxin - south
The aim of this study was to determine the presence of virulence genes in isolates of CTX-M Escherichia coli from diseased chickens, from healthy chickens and from urinary tract infections in people. Three CTX-M E. coli strains from three different instances of disease in poultry (two of which were E. coli related) were tested for blaCTX-M sequence type and replicon type. Additionally, they were tested for the presence of 56 virulence genes (encoding fimbriae, adhesins, toxins, microcins and iron acquisition genes) using a micro-array. Results were compared to the virulence genes present in isolates from 26 healthy chickens and from 10 people with urinary tract infections. All genes found in isolates from diseased birds, including the astA (heat stable toxin) and tsh (temperature sensitive haemagglutinin) genes which have previously been associated with colibacillosis in chickens, were also present in isolates from healthy birds. However, 6/10 of the virulence genes found were exclusive to isolates from humans. Genes exclusive to chicken isolates included ireA (sidephore receptor), lpfA (long polar fimbriae), mchF (microcin transporter protein) and tsh whilst genes exclusive to human isolates included ctdB (cytolethal distending toxin), nfaE (non-fimbrial adhesion), senB (plasmid encoded enterotoxin) and toxB (toxin B). The results support previous findings that CTX-M E. coli strains in chickens are generally different from those causing disease in humans, but genes such as astA and tsh in isolates from diseased birds with colisepticaemia were also present in isolates from healthy birds
Increased detection of extended spectrum beta-lactamase producing Salmonella enterica and Escherichia coli isolates from poultry
Dierikx, C.M. ; Essen-Zandbergen, A. van; Veldman, K.T. ; Smith, H.E. ; Mevius, D.J. - \ 2010
Veterinary Microbiology 145 (2010)3-4. - ISSN 0378-1135 - p. 273 - 278.
gram-negative bacteria - resistance plasmid - ctx-m - enterobacteriaceae - animals - cephalosporins - identification - typhimurium - strains - genes
To gain more information on the genetic basis of the rapid increase in the number of isolates exhibiting non-wild type Minimum Inhibitory Concentrations (MICs) for cefotaxime observed since 2003, beta-lactamase genes of 22 Salmonella enterica and 22 Escherichia coli isolates from broilers in 2006 showing this phenotype were characterized by miniaturized micro-array, PCR and DNA-sequencing. Presence and size of plasmids were determined by S1-digest pulsed-field gel electrophoresis and further characterized by PCR-based replicon typing. Transfer of resistance plasmids was tested by conjugation and transformation experiments. To link resistance genes and plasmid type, Southern blot hybridization experiments were conducted. In 42 isolates, five (blaCTX-M-1, blaCTX-M-2, blaTEM-20, blaTEM-52, blaSHV-2) different extended spectrum beta-lactamase (ESBL)-genes and two (blaACC-1, blaCMY-2) AmpC-genes were present. Three of the detected ESBL-genes (blaCTX-M-1, blaTEM-52 and blaCTX-M-2) were located on similar types of plasmids (IncI1 and IncHI2/P) in both E. coli and Salmonella. Two other detected ESBL- and AmpC-genes blaSHV-2 and blaCMY-2 respectively (on IncK plasmids), were only found in E. coli, whereas the AmpC-gene blaACC-1 (on non-typable plasmids), and the ESBL-gene blaTEM-20 (on IncI1 plasmids), were only detected in Salmonella. In two isolates, no ESBL- or AmpC-gene could be detected through these methods. The increase in the number of E. coli and S. enterica isolates from the gastro-intestinal tract of broilers exhibiting non-wild type MICs for cefotaxime is mainly due to an increase in IncI1 plasmids containing blaCTX-M-1. The reason for the successful spread of this plasmid type in these species is not yet understood.
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