High prevalence and diversity of Extended-Spectrum β-Lactamase and emergence of Carbapenemase producingEnterobacteriaceaespp in wildlife in Catalonia

AbstractIn wildlife, most of the studies focused on antimicrobial resistance (AMR) describeEscherichia colias the principal indicator of the selective pressure. In the present study, new species ofEnterobacteriaceaewith a large panel of cephalosporin resistant (CR) genes have been isolated from wildlife in Catalonia. A total of 307 wild animals were examined to determine CR enterobacteria prevalence, AMR phenotypes and common carbapenem and CR gene expression. The overall prevalence of CR-phenotype was 13% (40/307): 17.3% in wild mammals (18/104) and 11.5% in wild birds (22/191) (p<0.01)). Hedgehogs presented the largest prevalence with 13.5% (14/104) of the mammal specimens, followed by raptors with 7.3% (14/191) of the total bird specimens. Although CRE. coliwas obtained most frequently (45%), other CR-Enterobacteriaceaespp likeKlebsiella pneumoniae(20%),Citrobacter freundii(15%),Enterobacter cloacae(5%),Proteus mirabilis(5%),Providenciaspp (5%) andSerratia marcescens(2.5%) were isolated. A high diversity of CR genes was identified among the isolates, with 50% yieldingblaCMY-2, 23%blaSHV-12, 20%blaCMY-1 and 18%blaCTX-M-15. Additionally, new CR-gene variants and resistance to carbapenems associated to OXA-48 were found. Most of the CR isolates, principallyK. pneumoniaeandC. freundii, were multiresistant with co-resistance to fluoroquinolones, tetracycline, sulphonamides and aminoglycosides. This study describes for the first time in wildlife a high prevalence ofEnterobacteriaceaespp harbouring a large variety of carbapenem and CR genes frequently associated to nosocomial human infections. Implementation of control measures to reduce the impact of anthropogenic pressure in the environment is urgently needed.