MICROBIOLOGICAL METHODS Evaluation of the GENE-UP V R Listeria spp. Method for the Detection of Listeria Species in a Variety of Foods and Select Environmental Surfaces: Collaborative Study, First Action 2019.10 Ronald Johnson, 1, * John Mills, 1 Jean-Louis Pittet, 2 Olivier Mathia, 3 Patrick Bird, 4 and Maria Nelson 4 1 bioMe ´ rieux. Inc., 595 Anglum Rd, Hazelwood, MO 63042, USA, 2 bioMe ´ rieux, Inc., Chemin de l’Orme, 69280 Marcy L’Etoile, France, 3 Institut Scientifique d’Hygie ` ne & d’Analyse, 17 rue Doyen Denis Leroy, 35000 Rennes, France, 4 AOAC INTERNATIONAL, 2275 Research Blvd. #300, Rockville, MD 20850, USA *Corresponding author’s e-mail: Ron.johnson@biomerieux.com Abstract Background: The GENE-UP V R Listeria spp. 2 (LIS 2) assay (Performance Tested Method SM 121803) is a real-time PCR molecular detection method for the rapid detection of Listeria species (Listeria monocytogenes, L. innocua, L. ivanovii, L. seeligeri, and L. welshimeri) in a variety of foods and environmental surfaces. Objective: The purpose of this validation was to evaluate the method’s interlaboratory performance and submit the results to AOAC INTERNATIONAL for adoption as First Action Official Method SM for the detection of Listeria species in a variety of foods and select environmental surfaces. Method: The GENE-UP method was evaluated in a multi-laboratory study as part of the AFNOR NF VALIDATION certification process using unpaired test portions for one food matrix, full-cream goat milk cottage cheese (8.4% fat). The candidate method was compared to the ISO 11290–1/Amd.1 reference method. Sixteen participants from 15 laboratories throughout the European Union participated. Three levels of contamination were evaluated: a non-inoculated control level (0 CFU/test portion), a low contamination level (2 CFU/test portion), and a high contamination level (10 CFU/test portion). Data from that study were analyzed according to the probability of detection (POD) statistical model. Results: The dLPOD C values with 95% confidence intervals between the candidate and reference method results were 0.02 (0.07, 0.03), 0.08 (0.31, 0.16), and 0.00 (0.03, 0.03) for the non-inoculated, low, and high contamination levels, respectively. Conclusions: The dLPOD C results demonstrate no difference in performance between the candidate method and reference method for the matrix evaluated. Highlights: Data from a singular collaborative study was used to achieve adoption as an AOAC First Action Official Method for the detection of Listeria species in a variety of foods and select environmental surfaces. Received: 3 March 2020; Revised: 16 July 2020; Accepted: 16 July 2020 V C AOAC INTERNATIONAL 2020. All rights reserved. For permissions, please email: journals.permissions@oup.com 192 Journal of AOAC INTERNATIONAL, 104(1), 2021, 192–203 doi: 10.1093/jaoacint/qsaa103 Advance Access Publication Date: 9 September 2020 Article Downloaded from https://academic.oup.com/jaoac/article/104/1/192/5903383 by guest on 19 April 2022