title: Comparable high rates of extended-spectrum-beta-lactamase-producing Escherichia coli in birds of prey from Germany and Mongolia.
abstract: Frequent contact with human waste and liquid manure from intensive livestock breeding, and the increased loads of antibiotic-resistant bacteria that result, are believed to be responsible for the high carriage rates of ESBL-producing E. coli found in birds of prey (raptors) in Central Europe. To test this hypothesis against the influence of avian migration, we initiated a comparative analysis of faecal samples from wild birds found in Saxony-Anhalt in Germany and the Gobi-Desert in Mongolia, regions of dissimilar human and livestock population characteristics and agricultural practices. We sampled a total of 281 wild birds, mostly raptors with primarily north-to-south migration routes. We determined antimicrobial resistance, focusing on ESBL production, and unravelled the phylogenetic and clonal relatedness of identified ESBL-producing E. coli isolates using multi-locus sequence typing (MLST) and macrorestriction analyses. Surprisingly, the overall carriage rates (approximately 5%) and the proportion of ESBL-producers among E. coli (Germany: 13.8%, Mongolia: 10.8%) were similar in both regions. Whereas bla(CTX-M-1) predominated among German isolates (100%), bla(CTX-M-9) was the most prevalent in Mongolian isolates (75%). We identified sequence types (STs) that are well known in human and veterinary clinical ESBL-producing E. coli (ST12, ST117, ST167, ST648) and observed clonal relatedness between a Mongolian avian ESBL-E. coli (ST167) and a clinical isolate of the same ST that originated in a hospitalised patient in Europe. Our data suggest the influence of avian migratory species in the transmission of ESBL-producing E. coli and challenge the prevailing assumption that reducing human influence alone invariably leads to lower rates of antimicrobial resistance.
authors.affiliation: Veterinary Faculty, Institute of Microbiology and Epizootics, Freie Universität Berlin, Berlin, Germany. guenther.sebastian@fu-berlin.de
authors.forename: Sebastian
authors.initials: S
authors.lastname: Guenther
authors.forename: Katja
authors.initials: K
authors.lastname: Aschenbrenner
authors.forename: Ivonne
authors.initials: I
authors.lastname: Stamm
authors.forename: Astrid
authors.initials: A
authors.lastname: Bethe
authors.forename: Torsten
authors.initials: T
authors.lastname: Semmler
authors.forename: Annegret
authors.initials: A
authors.lastname: Stubbe
authors.forename: Michael
authors.initials: M
authors.lastname: Stubbe
authors.forename: Nyamsuren
authors.initials: N
authors.lastname: Batsajkhan
authors.forename: Youri
authors.initials: Y
authors.lastname: Glupczynski
authors.forename: Lothar H
authors.initials: LH
authors.lastname: Wieler
authors.forename: Christa
authors.initials: C
authors.lastname: Ewers
mesh_terms: D000818:Animals; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000201:enzymology* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary*; D005858:Germany; D017720:Molecular Epidemiology; D008986:Mongolia; D020304:Raptors / Q000382:microbiology*; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D001618:beta-Lactamases