Rapid and simultaneous detection of fluoroquinolone- and macrolide-resistant Campylobacter jejuni/coli in retail chicken meat using CAMpylobacter Express Resistance Array (CAMERA)

A rapid method for the simultaneous detection of fluoroquinoloneand macrolide-resistant Campylobacter jejuni/ coli in food products is long-awaited. In this study, we developed a DNA microarray-based method with primer extension, named CAMpylobacter Express Resistance Array (CAMERA). A series of oligonucleotide probes corresponding to each mutation in gyrA and rrl for fluoroquinolone and macrolide resistance, respectively, were selected and fixed on a membrane as capture probes for identifying C. jejuni/coli and detecting mutations conferring fluoroquinoloneand macrolide-resistance. The specificity was confirmed using 152 strains from livestock feces. Spiking of chicken meat samples revealed that CAMERA can detect 1-9 CFU/g C. jejuni/coli. Seventeen Campylobacter strains (16 C. jejuni and 1 C. coli) were isolated from 100 retail chicken meat samples via microbial culture. Using CAMERA, 16 of these 17 samples were positive for C. jejuni/coli, and the susceptibility to fluoroquinolone/macrolide could be determined (94% sensitivity and 100% specificity). The culture method requires more than 5-6 days for isolating C. jejuni/coli and determining antimicrobial susceptibility. In contrast, CAMERA requires <30 h from the beginning of the enrichment culture to the final determination of fluoroquinoloneand macrolide-resistant C. jejuni/coli. These results suggest that CAMERA is a rapid method for detecting C. jejuni/coli and is suitable for simultaneously determining the susceptibility to the two front-line drugs. This method may facilitate surveillance and control of fluoroquinoloneand macrolide-resistant C. jejuni/coli contamination in retail chicken meat.