Comparison of a real-time polymerase chain reaction assay with a culture method for the detection of Salmonella in retail meat samples

A real-time polymerase chain reaction (PCR) method developed in this study was compared with a conventional International Organization for Standardization culture method for the detection of Salmonella in Irish beef, chicken, pork and turkey. This also provided a snapshot of the incidence of Salmonella in such products. After selective enrichment, all meat samples (n = 100) were: (1) subjected to DNA extraction and real-time PCR analysis using primers against Salmonella spp. specific gene (16S rRNA) or the invA virulence gene; and (2) plated on differential media and identified as Salmonella using immunological and sub-typing methods. Retail samples (5/100) were shown to contain Salmonella using the 16S rRNA gene-based real-time PCR assay and the standard culture method. However, only two (of five) samples were shown to contain Salmonella using the invA gene-based real-time PCR assay. For the sample set examined, the developed 16S rRNA gene-based real-time PCR assay demonstrated comparable specificity and sensitivity to the currently used standard culture method but was considerably more rapid.