Header

UZH-Logo

Maintenance Infos

Phenotypic and genotypic characteristics of Escherichia coli with non-susceptibility to quinolones isolated from environmental samples on pig farms


Kindle, Patrick; Zurfluh, Katrin; Nüesch-Inderbinen, Magdalena; von Ah, Sereina; Sidler, Xaver; Stephan, Roger; Kümmerlen, Dolf (2019). Phenotypic and genotypic characteristics of Escherichia coli with non-susceptibility to quinolones isolated from environmental samples on pig farms. Porcine Health Management, 5(1):9.

Abstract

Background: In the last decade, the growth of the pig-farming industry has led to an increase in antibiotic use, including several used in human medicine, e.g. (fluoro)quinolones. Data from several studies suggest that there is a link between the agricultural use of antibiotics and the prevalence of antibiotic-resistant bacteria in the pig farm environment, including (fluoro)quinolone resistance. This poses a threat to human and animal health. Our goal was to phenotypically and genotypically characterize 174 E. coli showing non-susceptibility to quinolones isolated from environmental samples from pig farms. Antimicrobial susceptibility testing (AST) was performed using the disk diffusion method. PCR and sequence analysis were performed to identify chromosomal mutations in the quinolone resistance-determining regions (QRDR) of gyrA and the isolates were screened for the presence of the plasmid-mediated quinolone resistance (PMQR) genes aac-(6')-Ib-cr, qepA, qnrA, qnrB, qnrC, qnrD and qnrS. Strain relatedness was assessed by phylogenetic classification and multilocus sequence typing (MLST).
Results: Of 174 isolates, 81% (n = 141) were resistant to nalidixic acid, and 19% (n = 33) were intermediately resistant. Overall, 68.4% (n = 119) were multidrug resistant. This study revealed a prevalence of 79.9% (n = 139) for gyrA QRDR mutations, and detected 21.8% (n = 38) isolates with at least one PMQR gene. The two most frequently detected PMQR genes were qnrB and qnrS (13.8% (n = 24) and 9.8% (n = 17, respectively). E. coli belonging to phylogenetic group A (48.3%/n = 84) and group B1 (33.3% /n = 58) were the most frequent. E. coli ST10 (n = 20) and ST297 (n = 20) were the most common STs.
Conclusions: E. coli with non-susceptibility to quinolones are widespread among the environment of Swiss pig farms and are often associated with an MDR phenotype. In several cases these isolates possess at least one PMQR gene, which could spread by horizontal gene transfer. E. coli from pig farms have diverse STs, some of which are associated with human and animal disease.

Abstract

Background: In the last decade, the growth of the pig-farming industry has led to an increase in antibiotic use, including several used in human medicine, e.g. (fluoro)quinolones. Data from several studies suggest that there is a link between the agricultural use of antibiotics and the prevalence of antibiotic-resistant bacteria in the pig farm environment, including (fluoro)quinolone resistance. This poses a threat to human and animal health. Our goal was to phenotypically and genotypically characterize 174 E. coli showing non-susceptibility to quinolones isolated from environmental samples from pig farms. Antimicrobial susceptibility testing (AST) was performed using the disk diffusion method. PCR and sequence analysis were performed to identify chromosomal mutations in the quinolone resistance-determining regions (QRDR) of gyrA and the isolates were screened for the presence of the plasmid-mediated quinolone resistance (PMQR) genes aac-(6')-Ib-cr, qepA, qnrA, qnrB, qnrC, qnrD and qnrS. Strain relatedness was assessed by phylogenetic classification and multilocus sequence typing (MLST).
Results: Of 174 isolates, 81% (n = 141) were resistant to nalidixic acid, and 19% (n = 33) were intermediately resistant. Overall, 68.4% (n = 119) were multidrug resistant. This study revealed a prevalence of 79.9% (n = 139) for gyrA QRDR mutations, and detected 21.8% (n = 38) isolates with at least one PMQR gene. The two most frequently detected PMQR genes were qnrB and qnrS (13.8% (n = 24) and 9.8% (n = 17, respectively). E. coli belonging to phylogenetic group A (48.3%/n = 84) and group B1 (33.3% /n = 58) were the most frequent. E. coli ST10 (n = 20) and ST297 (n = 20) were the most common STs.
Conclusions: E. coli with non-susceptibility to quinolones are widespread among the environment of Swiss pig farms and are often associated with an MDR phenotype. In several cases these isolates possess at least one PMQR gene, which could spread by horizontal gene transfer. E. coli from pig farms have diverse STs, some of which are associated with human and animal disease.

Statistics

Citations

Dimensions.ai Metrics
5 citations in Web of Science®
4 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

23 downloads since deposited on 05 Jun 2019
10 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:05 Vetsuisse Faculty > Institute of Food Safety and Hygiene
05 Vetsuisse Faculty > Veterinary Clinic > Department of Farm Animals
Dewey Decimal Classification:570 Life sciences; biology
630 Agriculture
Scopus Subject Areas:Health Sciences > Small Animals
Health Sciences > Food Animals
Life Sciences > Animal Science and Zoology
Health Sciences > Veterinary (miscellaneous)
Uncontrolled Keywords:Antimicrobial resistance; Escherichia coli; Fluoroquinolones; Genotypes; Pigs
Language:English
Date:1 December 2019
Deposited On:05 Jun 2019 15:16
Last Modified:26 Aug 2020 07:13
Publisher:BioMed Central
ISSN:2055-5660
OA Status:Gold
Free access at:PubMed ID. An embargo period may apply.
Publisher DOI:https://doi.org/10.1186/s40813-019-0116-y
PubMed ID:30867937

Download

Gold Open Access

Download PDF  'Phenotypic and genotypic characteristics of Escherichia coli with non-susceptibility to quinolones isolated from environmental samples on pig farms'.
Preview
Content: Published Version
Language: English
Filetype: PDF
Size: 680kB
View at publisher
Licence: Creative Commons: Attribution 4.0 International (CC BY 4.0)