Microbiology Methods for ERP Review 3-2020

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For the non-inoculated controls, 0 out of 132 samples (POD CP of 0.00) produced a presumptive positive result by the candidate method with 0 out of 132 test portions (POD CC and POD C of 0.00) confirming positive. For the reference method, 0 out of 132 portions were reported as positive (POD R of 0.00). A dLPOD C value of 0.00 with 95% confidence interval of (-0.03, 0.03) was obtained between the candidate and reference method, indicating no statistically significant difference between the two methods. A dLPOD CP value of 0.00 with 95% confidence intervals of (-0.02, 0.02) was obtained between presumptive and confirmed results indicating no statistically significant difference. Detailed results of the POD statistical analysis for the GENE-UP Salmonella method with traditional confirmation are presented in Table 2020.2B and Figures 2A – 2D. During the collaborative study, the candidate method was able to accurately detect and differentiate the target microorganism from high levels of competing background microflora from within the matrix. Several laboratories indicated that the high background microflora made identifying target organism difficult, even after sub-culturing in a secondary enrichment. These collaborators indicated the ease of use of the GENE-UP Salmonella method in detecting the pathogen would be very beneficial to their laboratory for matrices with high background microflora. Fifteen collaborators were solicited to participate in the study. One collaborator was unable to complete testing and did not submit results. A second collaborator did not perform the traditional confirmation procedure and therefore their data was not included. Two additional laboratories (1 and 10) were removed from data analysis due to contamination in their non- inoculated control samples. Discussion

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