Evaluation of two bacteriophage-based rapid diagnostic methods for Salmonella spp. detection
This study compares the PhageDx™Salmonella Assay (PhageDx assay) and VIDAS® UP Salmonella (SPT) assay for detecting Salmonella in selected food products. Both assays demonstrated equivalent specificity in detecting 107 Salmonella spp. isolates and 186 non-Salmonella strains from diverse genera. During testing of Salmonella in fresh cut romaine lettuce and raw ground turkey, the PhageDx assay was able to detect 0.2 to 2 CFU of Salmonella in 25 g lettuce and 375 g ground turkey after only 7 hours of incubation, which was significantly shorter than the 18 hours required by the SPT assay. Moreover, the performance of the PhageDx assay and the SPT assay was found to be statistically equivalent to the Canadian culture reference method MFHPB-20 (Chi-square < 3.84). Overall, this study demonstrates the PhageDx assay is a rapid and reliable tool for detecting Salmonella in selected food products and has a promising future to be a commercialized assay.