Microdilution testing reveals considerable and diverse antimicrobial resistance of Escherichia coli, thermophilic Campylobacter spp. and Salmonella spp. isolated from wild birds present in urban areas

Abstract

The antimicrobial resistance (AMR) of E. coli, Salmonella spp. and thermophilic Campylobacter spp. isolated from wild birds in the Austrian-Czech border region, predominantly within the vicinity of Vienna and Brno, was determined. Bacteria were isolated from cloacal swabs taken from 53 avian species belonging to 14 orders, the majority being feral pigeons and various songbirds. Consequently, 1978 E. coli, 24 Salmonella and 99 Campylobacter isolates were tested by microdilution method against a panel of 14 (E. coli and Salmonella spp.) or ten antimicrobial substances (Campylobacter spp.). The AMR varied greatly between Austrian and Czech isolates, between different bird and bacterial species and between the different antimicrobials without consistent trends being recognizable. In 331 from 664 birds, differences in the AMR profile between the two or three E. coli isolates from the same bird were observed. Concerning E. coli, the least effective antimicrobial was cephalotin (90.8% of isolates resistant); for Campylobacter it was trimethoprim-sulfamethoxazole (71.4% of isolates resistant). None of the antimicrobials was effective against all E. coli or Campylobacter isolates. In contrast, more than half of the antimicrobials were effective against all Salmonella isolates, but 71.4% of the Czech Salmonella isolates and all of the Austrian Salmonella isolates were multi-resistant (resistant to three or more antimicrobial substances); streptomycin being the least effective antimicrobial substance (90.5% of isolates resistant). It is concluded that AMR in zoonotic bacteria from wild birds in the investigated densely populated areas is widespread and diverse, arguing for certain care at the wildlifehuman interface, but AMR to clinically important and critical antimicrobials is relatively low.

Clinically relevant antimicrobial resistance at the wildlife–livestock–human interface in Nairobi: an epidemiological study

“…In this study, scavenging birds and water birds had longer antibiograms than all other wildlife species. Antimicrobial resistance-carriage in high proportions of water birds is a common finding in other parts of the world, 28 where, in the absence of natural habitats such as wetlands, these species forage on sewage treatment plants, rubbish dumps, and abattoir viscera ponds. Artificial habitats such as these are considered important routes for the dispersal of human-excreted and livestock-excreted antimicrobial resistance into the environment 11, 29…”

The Role of Gulls as Reservoirs of Antibiotic Resistance in Aquatic Environments: A Scoping Review

“…Palmgren et al (2006) ringed gulls and sampled 1,047 individuals for up to 3 years. This study failed to detect long-term carriage of antibiotic-resistant Salmonella since Papagiannitsis et al, 2017;Vergara et al, 2017;Vittecoq et al, 2017;Ahlstrom et al, 2018Ahlstrom et al, , 2019aBarguigua et al, 2019; atricilla Poeta et al, 2008;Bonnedahl et al, 2009Rose et al, 2009;Hernandez et al, 2010;Simões et al, 2010;Veldman et al, 2013;Hasan et al, 2014;Stedt et al, 2015;Alcalá et al, 2016;Aberkane et al, 2016Aberkane et al, , 2017Atterby et al, 2016Atterby et al, , 2017Dolejska et al, 2016;Liakopoulos et al, 2016;Merkeviciene et al, 2017Merkeviciene et al, , 2018Papagiannitsis et al, 2017;Troxler et al, 2017;Vergara et al, 2017;Ahlstrom et al, 2018Ahlstrom et al, , 2019aAhlstrom et al, ,b, 2021Mukerji et al, 2019Mukerji et al, , 2020 all positive individuals were negative during the sampling 2 months later.…”

Contrasting patterns of Campylobacter and Salmonella distribution in wild birds: a comparative analysis

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