AUTHOR=Haenni Marisa , Métayer Véronique , Jarry Romane , Drapeau Antoine , Puech Marie-Pierre , Madec Jean-Yves , Keck Nicolas 

TITLE=Wide Spread of blaCTX–M–9/mcr-9 IncHI2/ST1 Plasmids and CTX-M-9-Producing Escherichia coli and Enterobacter cloacae in Rescued Wild Animals

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.601317

DOI=10.3389/fmicb.2020.601317

ISSN=1664-302X

ABSTRACT=<p>Wildlife has recently been pinpointed as one of the drivers of dissemination of genes conferring resistances to clinically important antimicrobials. The presence of both extended-spectrum beta-lactamase- (ESBL) and carbapenemase-encoding genes has notably been reported in wild birds, that can act as sentinels of antimicrobial resistance (AMR) contamination but also as long-distance spreaders in case of migratory birds. Here, 424 wild birds brought to a rescue center in France were sampled over a 6-month period. These birds encompassed 62 different sedentary or migratory species. A further 16 wild mammals present in the center were also investigated. No carbapenemase-producer was found, but we identified a surprisingly high proportion (24.1%) of ESBL-positive isolates. A total of 144 non-duplicate isolates were collected, including <italic>Escherichia coli</italic> (<italic>n</italic> = 88), <italic>Enterobacter cloacae</italic> (<italic>n</italic> = 51), and <italic>Citrobacter freundii</italic> (<italic>n</italic> = 5), of which 123 carried the <italic>bla</italic><sub>CTX–M–</sub><sub>9</sub> gene. PFGE, phylogroup, and MLST revealed the presence of a limited number of ESBL-positive clones circulating in these animals, all presenting multiple associated resistances. Next-generation sequencing on a subset of isolates, followed by Southern blot hybridization, showed the wide dissemination of an IncHI2/ST1 plasmid carrying the <italic>bla</italic><sub>CTX–M–</sub><sub>9</sub>, <italic>bla</italic><sub>SHV–</sub><sub>12</sub> and <italic>mcr-9</italic> genes. In all, our results undoubtedly reflect cross transmissions of ESC-resistance (ESC-R) Enterobacteriaceae within the rescue center – similarly to nosocomial spreads observed at hospital, rather than the true bacterial flora of birds. We also showed that the spread of ESC-R in this rescue center did not only rely on clonal but also on a highly successful plasmidic transmission. Since most animals are intended to get back to nature after a few days or weeks, this is obviously an issue with regard to ESBL dissemination in natural environments.</p>