The 3M<sup>™</sup> Molecular Detection Assay (MDA) 2 <em>- Listeria </em>uses loop-mediated isothermal amplification and bioluminescence detection to rapidly detect <em>Listeria </em>spp. in a broad range of food types and environmental surfaces. Using an unpaired study design, the MDA 2 - <em>Listeria </em>was compared to the U.S. Department of Agriculture Food Safety and Inspection Service <em>Microbiology Laboratory Guidebook </em>Chapter 8.09 "<em>Isolation and Identification of Listeria monocytogenes from Red Meat, Poultry, and Egg Products, and Environmental Samples</em>" reference method for the detection of <em>Listeria </em>in deli turkey and raw chicken breast fillet. Technicians from 13 laboratories located within the continental United States and Canada participated in the collaborative study. Each matrix was evaluated at three levels of contamination: an uninoculated control level (0 CFU/test portion), a low inoculum level (0.2-2 CFU/test portion), and a high inoculum level (2-5 CFU/test portion). Statistical analysis was conducted according to the probability of detection (POD) statistical model. Results obtained for the low inoculum level test portions produced a difference in collaborating laboratory POD (dLPOD) value of 0.04 with a 95% confidence interval of (-0.08, 0.17) for deli turkey, indicating that the difference between methods was not statistically significant at the 0.05 probability level. For raw chicken breast fillet, a dLPOD value of 0.16 with a 95% confidence interval of (0.04, 0.28) indicated a statistically significant difference, with an observed higher proportion of positive results by the candidate method than the reference method.
PMID: 28059049 [PubMed - as supplied by publisher]