To detect the presence of the ermB gene associated with macrolide resistance in Campylobacter spp. strains isolated from chickens marketed in Lima, Peru.
120 samples of chicken skin from three markets in the districts of San Martin de Porres (n = 30), Santa Anita (n = 20), and Independencia (n = 70), located in the Province of Lima, Peru, were analyzed. Microbiological analysis of the samples was carried out according to ISO standard 10272-1:2017. For the polymerase chain reaction (PCR) confirmation of genus and species, 16-rRNA and GlyA and hipO primers, respectively, were used. For the evaluation of antibiotic sensitivity, the Müller-Hinton agar with 5% blood, with sensi-discs for azithromycin (15 μg) and erythromycin (15 μg), was used. For detection of the ermB gene in strains with resistant phenotypes, conventional PCR was used.
A total of 117 positive samples (97.5%) were obtained; of these, 100% were compatible with Campylobacter coli (negative hippurate test) and confirmed by PCR. The plate-based assessment of antibiotic resistance to azithromycin and erythromycin resulted in 100% of strains with a phenotype that is resistant to these macrolides, while the PCR to detect the ermB gene indicated a total of 62 positives (53%), which were confirmed through sequencing.
These results demonstrate that the chicken carcasses sold in markets in Lima present contamination by C. coli with high resistance to macrolides, which can be attributed to the presence of the ermB gene.