Purpose: The purpose of these studies was to comparatively evaluate the accuracy of the Atlas Salmonella SEN Detection Assay and BAX Salmonella Assays (original and real-time) for the detection of Salmonella enterica in production ground poultry products.
Methods: Ground poultry products, consisting of ground turkey (n = 39) and ground chicken (n = 4), were collected by two poultry processors. Sample weights ranging from 25 to 325g were enriched utilizing Buffered Peptone Water (BPW) in a 1:10 dilution at 35° ± 2°C. For the Atlas method, 400 µl was transferred into sterile sample transfer tube at 12 hours (Processor B) and at 18-24 hours (Processor A). Both processors conducted BAX analysis as per routine procedure on the paired enrichments at 20-24 hours. Duplicate 1.5-2.0 ml aliquots from the enrichments were sampled into sterile vials, maintained at 4°C, and shipped to Roka for cultural analysis. Atlas and culture results were reported to collaborators at which time BAX results were disclosed.
Results: In total, Salmonella enterica was identified in 27.91% of samples by culture analysis, in 25.58% by the Atlas assay and in 16.28% by the BAX assay. The BAX assay reported 5 false negative results and the Atlas assay report 1 false negative result as compared to culture on ground poultry samples. Percent agreement of the screening tests to culture for the Atlas and BAX Salmonella assays were 97.67% and 88.37%, respectively.
Significance: Screening method performance and accuracy can be adversely affected by matrix characteristics, variation in sample preparation procedures, and the rapid detection method utilized.