Producing Extended-Spectrum β-lactamases (ESBL) from Domestic Camels in the Canary Islands: A One Health Approach.

Objective: This work aimed to determine the carriage rate of ESBL-producing as well as their genetic characteristics in camels from the Canary Islands, Spain.

Methods: Fecal samples were recovered from 58 healthy camels from Gran Canaria (n = 32) and Fuerteventura Islands ( = 26) during July 2019. They were seeded on MacConkey (MC) agar no supplemented and supplemented (MC + CTX) with cefotaxime (2 µg/mL). Antimicrobial susceptibility was determined by disk diffusion test (CLSI, 2018). The presence of , , and genes was tested by PCR/sequencing. Furthermore, the 1 (colistin resistance), A/B (tetracycline resistance), 1 (integrase of class 1 integrons) and genes were analyzed. Phylogenetic groups and sequence types were determined by specific-PCR/sequencing for selected isolates.

Results: was obtained from all the 58 camels in MC media (100%) and in five of them in MC + CTX media (8.6%). Furthermore, 63.8% of isolates recovered from MC agar were susceptible to all the antibiotics tested. The five isolates recovered from MC + CTX media were characterized and two of them were ESBL-producers (3.4%). Both ESBL-producer isolates carried the gene and belonged to the lineages ST3018 (phylogroup A) and ST69 (phylogroup B1). The 3 ESBL-negative isolates recovered from MC-CTX plates were ascribed to phylogroup-B.

Conclusions: Camels can be a source of ESBL-producer bacteria, containing the widespread gene associated with the lineages ST3018 and ST69.