Validation of the ANSR® for Campylobacter Method for Detection of Thermophilic Campylobacter spp. in Chicken Carcass Rinse and Turkey Sponge Samples.

Abstract

A performance validation of the ANSR® for Campylobacter method was conducted in selected matrixes. This assay used selective nicking enzyme amplification technology to amplify target genes. Samples were enriched for 20 to 24 h and then lysed. The assay was completed within 50 min using real-time detection in a combination incubator/fluorescence detector and software. When 50 distinct strains of Campylobacter jejuni, C. lari, or C. coli were tested for inclusivity, all 50 strains produced positive results. In exclusivity testing, 31 strains of related organisms, including seven nontarget Campylobacter strains and other common species, were evaluated. All 31 species generated negative ANSR assay results, including the nontarget Campylobacter strains. The ANSR for Campylobacter method was compared to the U.S. Department of Agriculture, Food Safety and Inspection Service Microbiology Laboratory Guidebook reference method using naturally contaminated chicken carcass rinse or turkey carcass sponge samples. ANSR method performance was not statistically different from the reference method using two different enrichment options. Equivalent results were observed at both time points (20 and 24 h) and in both atmospheres (microaerobic and aerobic) to reference methods. Method performance with chicken carcass rinse was confirmed in an independent laboratory study. Additionally, in robustness testing, small, deliberate changes to the assay parameters minimally affected ANSR method performance. Finally, accelerated stability results from three independently manufactured lots supported a shelf life of 6 months when stored at 4°C. The ANSR assay offered greater efficiency and flexibility when compared to the reference method with a 20-24 h single-step enrichment in a microaerobic or an aerobic atmosphere.