Longitudinal Study on Extended-Spectrum Beta-Lactamase-E. coli in Sentinel Mallard Ducks in an Important Baltic Stop-Over Site for Migratory Ducks in Germany

Abstract

Antimicrobial resistance (AMR) is a serious global health threat with extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales as the most critical ones. Studies on AMR in wild birds imply a possible dissemination function and indicate their potential role as sentinel animals. This study aimed to gain a deeper insight into the AMR burden of wild waterfowl by sampling semi-wild mallard ducks used as sentinels and to identify if AMR bacteria could be recommended to be added to the pathogens of public health risks to be screened for. In total, 376 cloacal and pooled fecal samples were collected from the sentinel plant over a period of two years. Samples were screened for ESBL-carrying E. coli and isolates found further analyzed using antimicrobial susceptibility testing and whole-genome sequencing. Over the sampling period, 4.26% (16/376) of the samples were positive for ESBL-producing E. coli. BlaCTX-M-1 and blaCTX-M-32 were the most abundant CTX-M types. Although none of the top global sequence types (ST) could be detected, poultry-derived ST115 and non-poultry-related STs were found and could be followed over time. The current study revealed low cases of ESBL-producing E. coli in semi-wild mallard ducks, which proves the suitability of sentinel surveillance for AMR detection in water-associated wildlife.

Investigating Environmental Matrices for Use in Avian Influenza Virus Surveillance—Surface Water, Sediments, and Avian Fecal Samples

“… a See Fig. 4 for depiction of site on map; A to D, samples originating from HPAI outbreak holdings; holding C is the site of a mallard sentinel station ( 60 ). The numbering corresponds with the sample IDs given in Table 2 .…”

Prevalence of Antibiotic Resistance and Virulence Genes in Escherichia coli Carried by Migratory Birds on the Inner Mongolia Plateau of Northern China from 2018 to 2023

“…Migratory birds are known to carry antibiotic-resistant E. coli [ 29 ]. Waterfowl can be considered sentinels of AMR in the environment [ 30 ]. E. coli is an excellent indicator species for studying the spread of AMR at the wildlife–livestock–human interface.…”

Surface water in Lower Saxony: A reservoir for multidrug-resistant Enterobacterales

“…Interestingly, bla CTX-M-32 was detected in a river upstream of the city, a gene that had not previously been reported from surface waters. It has been identified in wild mallard and slaughterhouse wastewater in Germany [ 36 , 37 ]. Detection of this gene in the respective area could indicate a potential contamination from wildlife or livestock.…”