Antimicrobial susceptibility and pathogenicity of C. coli strains isolated from humans and chicken food chain

Resumen del trabajo presentado al 7th Congress of European Microbiologists, celebrado en Valencia (España) del 9 al 13 de julio de 2017.[Background]: Campylobacter is the leading cause of bacterial food-borne gastroenteritis worldwide and the species C. jejuni and C. coli cause more than 95% of the infections attributed to this genus. In the European Union, campylobacteriosis was the most commonly reported bacterial zoonosis, with 236,851 confirmed human cases in 2014. Although C. jejuni is the most diagnosed species, in the last years C. coli has become increasingly important, mainly due to the high antibiotic resistant levels. [Objectives]: To study the incidence and virulence of C. coli and its relationship with the human infection in 201 Campylobacter strains isolated from the chicken food chain and humans patients. [Methods and Results]: The response to 14 different antibiotics was analyzed following the Kirby-Bauer. The results obtained showed that C. coli had the highest levels of drug multiresistance (MRD) with an 84.6%. They also presented a 20.5% of resistance to erythromycin (Ery-R) among human isolates, the first therapeutic option in campylobacteriosis. The presence of three relevant genes associated to Campylobacter virulence ( cdtABC complex, ciaB and virB11) were investigated in C. coli strains. ciaB polymorphisms found in the food chain strains suggested that infective strains could be from a source other than chicken meat. Chicken strains clustered in a unique clone after MLST+flaA typing of C. coli strains. Data suggest that a significant proportion of human isolates might be considered of no-chicken origin. [Conclusions]: C. coli MRD-EryR isolated from humans with no-chicken origin could be an emerging risk for the European consumer.Peer Reviewe