Recognising that sensitive and more cost-effective methods are needed for detecting food-borne pathogens, we are launching a project seeking to validate and standardise use of the polymerase chain reaction (PCR) for this purpose. Although a powerful research tool, the application of PCR for detecting food-borne pathogens is hampered from lack of validation, standard protocols, reagents, and equipment. Additional specific project objectives include validating a simple method for purifying DNA from bacterial cultures, establishing a central collection of certified DNA sample materials, establishing a databank containing key food-pathogen DNA sequence, listing strains for specificity testing, developing standardised reagents, and validating pre-PCR sample treatment methods.
To facilitate its routine use for diagnostic purposes, participants in the new project are being asked to undertake a series of specific projects, including to construct a DNA sample library and primer databank, validate widely used thermocyclers and other automated equipment, and to develop uniform guidelines describing how tests should be conducted. Because much of the challenge in applying PCR to food-borne pathogens is technical, there is also a need to develop standardised training manuals and procedures for those who will conduct such tests.
The program is planned in 2 phases over a 3-year period and will include 6 work packages and 20 tasks. During phase 1, researchers working in 12 separate laboratories will develop data about the basic methods and requisite reagents. During phase 2, they will focus on validation trials, automation issues, and transferring the validated technology to end-users.
As part of this project, 35 participants are being asked to focus on 5 major pathogens--Salmonella, Campylobactor, enterohemorrhagic E. coli (EHEC), L. monocytogenes and Y. enterocolitica, and on three sample types: poultry carcass-rinse, pig carcass swab, and milk. An expert laboratory is assigned to each pathogen, with the task to prepare defined DNA material, compare the methods and devise and optimise a PCR detection protocol.