title: Relative accuracy, specificity and sensitivity of a 5' nuclease real-time PCR assay for Salmonella detection in naturally contaminated pork cuts.
abstract: In the present study the relative sensitivity, specificity and accuracy of a Real-Time PCR assay for Salmonella detection in naturally contaminated pork cuts were evaluated in comparison with the ISO 6579:2004 reference culture method. Meat samples were collected from packaging up to the end of shelf life from 10 different lots over a year. The PCR method included an 18 h pre-enrichment step in buffered peptone water, a DNA extraction step, and a final 5' nuclease Real-Time PCR assay, including an Internal Amplification Control (IAC) and targeting the ttrRSBCA locus. Based on the analysis of 480 sub-units (three sub-units for each sample), the relative sensitivity, specificity and accuracy of the Real-Time PCR assay were 90, 78.7, and 82.9% respectively, corresponding to a Cohen's kappa value of 0.81 (very good agreement). These results suggest the PCR method as a rapid and accurate method for the quick check of meat lots before distribution. The ISO reference method might be applied only on positive Real-Time PCR samples for confirmatory and isolation purposes, mandatory in epidemiological investigations.
authors.affiliation: Department of Agricultural and Food Sciences, Alma Mater Studiorum, University of Bologna, Via del Florio 2, 40064 Ozzano dell'Emilia, BO, Italy.
authors.forename: Frédérique
authors.initials: F
authors.lastname: Pasquali
authors.affiliation: Department of Agricultural and Food Sciences, Alma Mater Studiorum, University of Bologna, Via del Florio 2, 40064 Ozzano dell'Emilia, BO, Italy. Electronic address: alessandra.decesare@unibo.it.
authors.forename: Alessandra
authors.initials: A
authors.lastname: De Cesare
authors.affiliation: Department of Agricultural and Food Sciences, Alma Mater Studiorum, University of Bologna, Via del Florio 2, 40064 Ozzano dell'Emilia, BO, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Bovo
authors.affiliation: Department of Veterinary Medical Sciences, Alma Mater Studiorum, University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell'Emilia, BO, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Serraino
authors.affiliation: Department of Agricultural and Food Sciences, Alma Mater Studiorum, University of Bologna, Via del Florio 2, 40064 Ozzano dell'Emilia, BO, Italy.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Manfreda
mesh_terms: D000818:Animals; D003257:Consumer Product Safety; D004269:DNA, Bacterial / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology / Q000379:methods; D008460:Meat / Q000382:microbiology*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D012015:Reference Standards; D012475:Salmonella / Q000302:isolation & purification*; D012680:Sensitivity and Specificity; D013552:Swine
chemical_list: D004269:DNA, Bacterial
keywords: Fresh meat; ISO method; Real-Time PCR; Salmonella