P1-43 Pathatrix Auto - the First AFNOR-approved Real-time PCR Method for Detecting Salmonella in Pooled Food Samples

Monday, August 4, 2014
Exhibit Hall D (Indiana Convention Center)
Jason Wall, Life Technologies, Inc., Austin, TX
Daniele Sohier, ADRIA Développement, Quimper, France
Rick Conrad, Life Technologies, Inc., Austin, TX
Introduction: The Pathatrix Auto™ pathogen isolation platform provides a workflow that is able to process as many as ten individual food enrichments in the same sample pool.  This sampling format has never been approved in the EU market, and would require extensive validation efforts by an expert testing lab to evidence that the approach is not only possible, but practical. 

Purpose: In order to validate this product for food safety testing in the EU, this workflow would need to demonstrate a relevant relative detection limit, show statistical similarity to the ISO 16140 reference through accuracy, sensitivity, and specificity; and prove its robustness and practicability in the field.

Methods: Adria Developpement was selected to perform the evaluation to ascertain the Pathatrix Auto’s ability to detect Salmonellain pooled food sample types by Real-time PCR and selective agar plating.  A Ring Trial proficiency study with 15 independent food safety testing labs was also conducted to verify that the workflow was functional and accurate with minimal training.  

Results: In both the Adria Developpement study and the Ring Trial, the candidate and reference methods were found to be statistically similar. Of the 202 different food sample types tested during this evaluation, a relative accuracy of 93.1%, a relative sensitivity of 87.7%, and a relative specificity of 96.7% was attained.  The relative detection limit was determined to be 0.4-1.5 log CFU/25g of sample, which was statistically similar to the reference.  The selected Ring Trial labs demonstrated 100% proficiency and accuracy in performing the workflow.

Significance: This is the first validated method for sample pooling in the EU.  The demonstrated robustness, accuracy, and ease of use of this workflow enables the user to rapidly screen for rare contamination events with high confidence, with up to a 90% cost savings over other PCR-based platforms.