Edited by: Gilberto Igrejas, University of Trás-os-Montes and Alto Douro, Portugal
Reviewed by: Azucena Mora Gutiérrez, Universidade de Santiago de Compostela, Spain; Jorge Blanco, Universidade de Santiago de Compostela, Spain; Liang Li, Los Angeles Biomedical Research Institute, United States
*Correspondence: Mashkoor Mohsin
This article was submitted to Antimicrobials, Resistance and Chemotherapy, a section of the journal Frontiers in Microbiology
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The increased presence of clinically relevant multidrug resistant bacteria in natural environments is an emerging challenge for global health care. Little is known regarding the occurrence of extended-spectrum beta-lactamase producing
The intensive use of antimicrobials in human and veterinary medicine has resulted in an emergence of antimicrobial resistance (AMR) in humans, animals and the environment at large (Radhouani et al.,
Previous studies have suggested the environment including water, soil and wildlife as the source for clinically relevant ESBL-
Recently, it has been suggested that certain clonal lineages distinguished by very low number of single nucleotide polymorphisms (SNPs) circulate at the human-animal-environment interfaces which strongly supports the One Health perspective of AMR (Falgenhauer et al.,
In a study conducted between 2013 and 2015, fecal samples of 150 wild migratory birds were collected from four wetland habitats in Pakistan (Figure
Sampling location and migratory routes of wild birds studied.
Confirmation of the ESBL production was done by double disc synergy test according to the CLSI guidelines (CLSI,
DNA extraction of confirmed ESBL-
WGS data from multiple bacterial isolates were analyzed simultaneously for their multi-locus sequence types (MLSTs), antibiotic resistance genes, plasmid replicon types and pMLST using the Bacterial Analysis Pipeline Tool at the web service of Center for Genomic Epidemiology (
For phylogenetic analysis, SNPs between the core genome of isolates were calculated using Harvest suite 1.0 (parsnp) (Treangen et al.,
Isolates displaying the pMLST type IncF[F-:A-:B53] were analyzed by S1-nuclease PFGE (Guerra et al.,
Twenty-six of 150 birds were fecal carriers of ESBL-producing
Characteristics of the ESBL producing
Pk-1 | Rosy Starling |
16/12/2013 | Balloki Headworks | CTX, CAZ, AMP, TE, SXT | ST-202 | IncFIB | IncF[F-:A-:B53] | n.d. | ||||||||||
Pk-2 | Rosy Starling |
16/12/2013 | Balloki Headworks | CTX, CAZ, AMP, C, DC, TE, ENR, MRB, SXT | ST-224 | No replicon | n.d. | |||||||||||
Pk-3 | Rosy Starling |
01/01/2014 | Trimmu headworks | CTX, CAZ, AMP, DC, TE, SXT | ST-10 | IncFIB | IncF[F-:A-:B53] | 130kb | ||||||||||
Pk-4 | Red-headed pocahard ( |
16/12/2013 | Balloki headworks | CTX, CAZ, AMP, DC, TE, SXT | ST-10 | IncFIB, IncI1 | IncF[F-:A-:B53], IncI1[Unknown ST] | 110/90kb | ||||||||||
Pk-5 | Eurasian coot ( |
11/02/2014 | Chashma barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-10 | IncY | n.d. | |||||||||||
Pk-6 | Eurasian coot ( |
11/02/2014 | Chashma barrage | CTX, CAZ, AMP,DC, TE, SXT | ST-4720 | IncFIC, IncI1, IncFIB, IncFII | IncI1[ST-3], IncF[F18:A-:B1] | n.d. | ||||||||||
Pk-7 | Eurasian coot ( |
11/02/2014 | Chashma barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-4720 | IncFIC, IncI1, IncFIB, IncFII | IncI1[ST-3], IncF[F18:A-:B1] | n.d. | ||||||||||
Pk-8 | Eurasian coot ( |
20/01/2014 | Chashma barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-7097 | IncFIB | IncF[F-:A-:B53] | 110/90kb | ||||||||||
Pk-9 | Eurasian coot ( |
20/01/2014 | Chashma barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-1722 | No replicon | n.d. | |||||||||||
Pk-10 | Red-headed pocahard ( |
16/12/2013 | Balloki headworks | CTX, CAZ, AMP | ST-58 | No replicon | n.d. | |||||||||||
Pk-11 | Eurasian coot ( |
11/02/2014 | Chashma barrage | CTX, CAZ, AMP | ST-361 | IncFIC, IncFIB, IncY | IncF[F46*:A-:B16] | n.d. | ||||||||||
Pk-12 | Eurasian coot ( |
11/02/2014 | Chashma barrage | CTX, CAZ, AMP, GM, TM, C, DC, TE, SXT | ST-602 | IncFIB, IncFIA, IncFIC, IncFII | IncF[F18:A5:B1] | n.d. | ||||||||||
Pk-13 | Eurasian coot ( |
11/02/2014 | Chashma barrage | CTX, CAZ, AMP, CO, PO, DC, TE, ENR, MRB, SXT | ST-354 | IncFII, IncHI2, IncFIB, IncFIA, IncI2 | IncHI2[ST-3], IncF[F36:A6*:B1] | n.d. | ||||||||||
Pk-14 | Eurasian coot ( |
11/02/2014 | Chashma barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-10 | IncY | n.d. | |||||||||||
Pk-15 | Mallard duck ( |
16/02/2015 | Rasul barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-1139 | IncFIB, p0111 | IncF[F-:A-:B53] | 130/100kb | ||||||||||
Pk-16 | Shoveler duck ( |
16/12/2013 | Balloki headworks | CTX, CAZ, AMP, GM, TM, ENR, MRB, SXT | ST-617 | ColRNAI | n.d. | |||||||||||
Pk-17 | Shoveler duck ( |
16/12/2013 | Balloki headworks | CTX, CAZ, AMP, DC, TE, SXT | ST-1303 | IncFIB | IncF[F-:A-:B53] | 130kb | ||||||||||
Pk-18 | Eurasian wigeon ( |
01/01/2014 | Trimmu headworks | CTX, CAZ, AMP, SXT | ST-2914 | IncFII, IncQ1, IncB/O/K/Z | IncF[F55*:A-:B-] | n.d. | ||||||||||
Pk-19 | Eurasian wigeon ( |
01/01/2014 | Trimmu headworks | CTX, CAZ, AMP, DC, TE, SXT | ST-3716 | IncFIB | IncF[F-:A-:B53] | 130kb/ 40kb | ||||||||||
Pk-20 | Mallard duck ( |
01/01/2014 | Trimmu headworks | CTX, CAZ, AMP, DC, TE, ENR, MRB, SXT | ST-1421 | IncFIB | IncF[F-:A-:B53] | 130/30kb | ||||||||||
Pk-21 | Mallard duck ( |
01/03/2014 | Chashma barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-7097 | IncFIB | IncF[F-:A-:B53] | 130/ 40/30kb | ||||||||||
Pk-23 | Mallard duck ( |
01/03/2014 | Chashma barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-93 | IncFIB | IncF[F-:A-:B53] | 60kb | ||||||||||
Pk-24 | Mallard duck ( |
16/02/2015 | Rasul barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-7097 | IncFIB | IncF[F-:A-:B53] | n.d. | ||||||||||
Pk-26 | Eurasian coot ( |
01/03/2014 | Chashma barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-7097 | IncFIB | IncF[F-:A-:B53] | 130/100kb | ||||||||||
Pk-29 | Eurasian coot ( |
01/03/2014 | Chashma barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-1139 | IncFIB, p0111 | IncF[F-:A-:B53] | 130/ 00kb | ||||||||||
Pk-30 | Eurasian coot ( |
01/03/2014 | Chashma barrage | CTX, CAZ, AMP, DC, TE, SXT | ST-93 | IncFIB | IncF[F-:A-:B53] | 60kb |
WGS revealed that all of 26 ESBL-
In this study, 17 different STs were observed among the 26 sequenced ESBL-
Core-genome based phylogenetic analysis of 26 isolates grouped
Whole Genome phylogeny based upon core genomes of 26 avian ESBL-
Wild migratory birds have been suggested as a reservoir of ESBL-producing
WGS showed
In fact, summing up the current literature it becomes obvious that the emergence of ESBL-producing
Besides their spread via plasmids, very recently the new trend of chromosomal integration of ESBL-encoding genes has been demonstrated in clinical
As mentioned above, wildlife has been reported to carry ExPEC strains, we therefore also screened for the occurrence of VAGs to gain information on pathotype. However, we detected no ExPEC strain in our isolates. Most of the strains harbored only a few VAGs and are likely commensal strains. However, all the
We found a large diversity of sequence types within the avian isolates including typical ESBL-associated sequence types like ST10, ST224, ST617 (Guenther et al.,
Interestingly we found identical STs in isolates originating from different avian host species and geographic locations (Figure
The transmission dynamics of ESBL-producing
MM, SG: conceived and designed the experiments; MM, SR, and FS: collected the data and samples; MM, KS, NR, FS, and PS: performed laboratory analysis; SG, MM, SR, and TS: analyzed the data; TS and SG: performed WGS; MM and SG: wrote the article. All authors have read and approved the final draft of the manuscript.
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
MM was supported by postdoctoral fellowship from the Alexander von Humboldt Foundation, Germany.
The Supplementary Material for this article can be found online at: