P3-173 Evaluation of Salmonella spp., Salmonella Enteritidis, and Salmonella Typhimurium Real-time PCR Kit Performance in Co-inoculated Poultry, Pork Meat, and Environmental Surface Samples

Wednesday, July 12, 2017
Exhibit Hall (Tampa Convention Center)
Jani Holopainen , Thermo Fisher Scientific , Vantaa , Finland
Katharine Evans , Thermo Fisher Scientific , Basingstoke , United Kingdom
David Crabtree , Thermo Fisher Scientific , Basingstoke , United Kingdom
Mikko Kauppinen , Thermo Fisher Scientific , Vantaa , Finland
Introduction: Thermo Scientific™ RapidFinder™ Salmonella Multiplex (Sp/SE/ST) PCR Kit is a real-time PCR based assay for the simultaneous detection and differentiation of Salmonella species, Salmonella Enteritidis, and Salmonella Typhimurium in poultry, pork, and environmental surface samples. The Salmonella Multiplex assay workflow includes a simple 15 minute sample lysis step followed by a 45 minute PCR run on the Applied Biosystems™ 7500 Fast or QuantStudio 5 Real-Time PCR instruments.

Purpose: The purpose of the study was to verify performance of the Salmonella Multiplex assay when poultry, pork, and environmental surface samples were co-inoculated with low levels of two Salmonella serovars S. Enteritidis and S. Typhimurium or Salmonella Kentucky. Presumptive results were compared to those obtained with the multiplex assay’s culture confirmation and the USDA FSIS Salmonella reference method.

Methods: Ten poultry, pork, and surface swab samples were co-inoculated with low levels of two Salmonella serovars to achieve fractionally positive results in accordance with AOAC guidelines. All samples analyzed with the Salmonella Multiplex Kit were enriched in Buffered Peptone Water (ISO formulation) + 12mg/L Novobiocin at 41.5oC for 14-16 hours, lysed, tested, and analyzed according to the protocol described in the instructions for use. Presumptive positive results were confirmed using culture and serological confirmation methods. The reference method was performed according to the USDA FSIS guidelines.

Results: The Salmonella Multiplex assay method proved to be an accurate method even when samples were contaminated with multiple Salmonella serovars. The assay was 100% sensitive and 100% specific versus culture and serological confirmation. Detection of two serovars from a single sample was possible from poultry, pork, and surface swabs.

Significance: The study demonstrated that the RapidFinder™ Salmonella Multiplex assay is a rapid, easy-to-use, and reliable workflow for the detection of Salmonella spp., S. Enteritidis, and S. Typhimurium in poultry, pork, and environmental surface samples.