About FDA
Rapid Testing and Identification of Salmonella in Foods
Description: CFSAN scientists are developing, evaluating, and deploying rapid and portable technologies capable of identifying unique variants of Salmonella directly from foods and environmental surfaces as well as from pure cultures. Current methodologies can take over two weeks to complete the detection, serotyping, and molecular epidemiologic evaluation of bacterial pathogens associated with foodborne illness. The genetic detection technologies under development here will sharply decrease the investigatory time necessary to connect a suspect food source to a specific Salmonella strain. Such rapid approaches will aid in the prevention of foodborne illness associated with the US food supply by allowing for the timely response and removal of foods contaminated by this dangerous pathogen.
Accomplishment: This project spearheaded development and/or evaluation, and field deployment of several rapid and modern approaches designed to detect, identify, and track Salmonella strains associated with contamination of the food supply. Some of these methods have greatly enhanced the speed at which a food or environmental sample can be analyzed for contamination by Salmonella, a common and dangerous bacterial foodborne pathogen, or have provided a sharply improved ability to track foodborne Salmonella contamination back to its source. Several milestones from the project included: (1) spearheading deployment across FDA field laboratories of a CDC-designed rapid method for the same-day serotyping of Salmonella; (2) successfully reducing the number of days to detect, isolate, and identify Salmonella Enteritidis contamination of shell eggs from nine days to four with a detection limit as sensitive as a single cell; and (3) applying whole-genome sequencing of Salmonella to augment select foodborne outbreaks investigations. Next-generation sequencing of food-associated Salmonella will greatly improve our ability to identify and traceback sources of foodborne outbreaks involving this pathogen. Taken together, application of these strategies will allow for timely and more accurate response and removal of contaminated foods. In addition, many hundreds of the Salmonella genome sequences generated from this project aided in spawning “The 100K Genome Project”, an open-source database of foodborne pathogen genomes that is providing a critical roadmap forward for public-private development of investigative methods to quickly identify and trace food pathogens back to their source. Of note, “The 100K Genome Project’ recently won the Secretary’s Pick for the 2012 HHSInnovates Awards which recognize the most innovative breakthroughs in the Department of Health and Human Services for the year. See related links below.
Milestone Description | Milestone Date | Milestone Status | Milestone Completion Date |
---|---|---|---|
A. Deployment and Field Validation of Salmonella Rapid Detection and Identification Methods |
12/30/2010 |
Completed | 1/6/2011 |
i. Deployment of IBIS biosensors into at least one FDA field laboratory or one State public health laboratory and corresponding training of relevant personnel from these sites |
6/30/2010 |
Completed | 10/1/2010 |
ii. Deployment of CDC Bioplex-based serotyping assay to regional FDA field laboratories and sister centers (i.e., CVM) |
12/30/2010 |
Completed | 1/6/2011 |
B. Development and Evaluation of Rapid and High-Throughput Detection and Assays for Salmonella |
9/30/2011 (9/30/2012) (12/31/2012) |
Completed | 10/4/2012 |
i. Complete first design iteration of the Salmonella species and subspecies IBIS biosensor detection plate for specific identification of strains directly from food matrices |
3/30/2010 |
Completed | 3/25/2010 |
ii. Successful automation and mechanization of the IBIS analytical process from overnight enrichments to final identification of Salmonella strains |
6/30/2010 |
Completed | 9/15/2010 |
iii. Completion of the first iteration of the IBIS food plate for detection of E. coli O157:H7, Salmonella, Listeria monocytogenes, and Shigella spp. from fresh cut produce |
3/30/2011 |
Completed | 3/29/2011 |
iv. Completion of design of multiplex real-time PCR assay for the ABI 7500 for rapid detection of Salmonella directly from overnight enriched produce |
6/30/2011 |
Completed | 10/15/2010 |
v. Completion of development of real-time PCR-based detection assay for S. Enteritidis directly from shell eggs |
3/31/2011 |
Completed | 12/16/2010 |
vi. Completion of evaluation and pre-collaborative validation of SE real-time PCR test |
9/30/2011 (9/30/2012) (12/31/2012) |
Completed | 10/4/2012 |
a. Complete processing of egg sample cultures and preparatory DNA pellets |
4/30/2012 |
Completed | 4/30/2012 |
b. Complete qPCR validation for 5 of the 10 planned validation trials |
7/31/2012 |
Completed | 8/10/2012 |
c. Complete additional qPCR validation trials and egg-based qPCR SE detection method |
9/30/2012 |
Completed | 9/5/2012 |
d. Complete statistical data analysis and coordination and compiling of pre-collaborative validation data for final report to ORS management and Center science leads |
12/31/2012 |
Completed | 10/4/2012 |
C. Development and/or Evaluation of Salmonella Molecular Serotyping Assays: |
9/30/2011 |
Completed | 10/5/2011 |
i. Completion of evaluation of Premitest PCR-array rapid serotyping assay |
9/30/2010 |
Completed | 1/11/2011 |
ii. Completion of preliminary evaluation of CDC Bioplex-based Salmonella serotyping scheme |
9/30/2010 |
Completed | 9/1/2010 |
iii. Use next generation whose genome sequencing approaches to build a database of complete genomes from the 50 Salmonella serotypes most often associated with human disease; use the database to design better tests |
6/30/2011 |
Completed | 10/5/2011 |
iv. Completion of the first iteration of the Salmonella serotyping plate for detection and identification of the top 20 Salmonella serovars associated with the food supply |
9/30/2011 |
Completed | 9/23/2011 |
Foot Notes
- The dates in italics under the milestone due dates are modified milestone due dates which had to be updated due to real-time delays. The milestone status reflects the revised dates.
Key Projects Legend
Milestone Status | Definition |
---|---|
Not Yet Started | Work for specific milestone has not yet been started. |
Completed | Milestone and/or overall project is completed. |
On Track | Milestone - On track for completion by milestone deadline. Quarter status - Project is on track for completion based on overall milestone status. |
On Hold | Milestone - On hold, but deadline for completion has not passed. Quarter status - Project is on hold, based on overall milestone status. |
Delayed | Milestone - Delayed as it has not been completed and deadline has passed. Quarter status - Project is delayed based on overall milestone status. |