Antimicrobial resistance in wildlife: detection of β-lactam/carbapenem resistance genes in European hedgehogs (Erinaceus europaeus, Linnaeus 1758) in Italy

In the last decades, increasing interest has turned to wild animals living in close contact with humans, pets or livestock, to evaluate their role as sentinels of environmental antimicrobial resistance pollution or potential reservoirs/vectors of antimicrobial-resistant bacteria/antimicrobial resistance genes. The aim of this study was to investigate the presence of β-lactam (including carbapenem) and colistin resistance genes in intestinal samples from 84 European hedgehogs (Erinaceus europaeus L. 1758, Mammalia: Erinaceomorpha) collected in central Italy. Unlike most studies based on bacterial isolates, a culture-independent approach was applied, allowing the detection of antimicrobial resistance genes also in non-culturable bacteria. Total DNA from intestinal fragments and faecal material was investigated by PCRs targeting the blaTEM, blaCTX−M, blaSHV, blaOXA−48 and mcr-1 genes. PCR positivity for β-lactam/carbapenem resistance genes was observed in 46 (55%) of the 84 tested animals. In 26 of 46 positive samples, two or more resistance genes were detected. No positive detections of the mcr-1 gene were obtained. The results confirm the potential role of the hedgehog as an environmental sentinel of antimicrobial-resistant bacteria or antimicrobial resistance genes.