Introduction Foodborne disease is estimated to cause 76 million illnesses and 5,000 deaths annually in the United States [1]. Of the known pathogens that cause foodborne illness, , O157:H7, , and are among the short list of micro-organisms that exert the largest disease burden. Bacteriological culturing has traditionally been used to detect microbial patho- gens in food, and this technique is still in widespread use today. However, the time-consuming and low-throughput nature of culture-based detection methods warrant their replacement by more rapid methods based on biomolecular analysis, like the polymerase chain reaction (PCR). PCR, predicated on DNA synthesis and amplification, is an established, core technique in molecular biol- ogy, microbiology, diagnostics, genetics and environmental science applications.
A derivative of PCR, real-time quantitative PCR (Q-PCR) kinetically monitors the reaction in ‘real time’. Q-PCR confers significant advantages over conventional PCR, including increased reaction speed, sensitivity and specificity; it also eliminates the need to open the reaction tubes for post-PCR analysis, thus preventing cross-contamination. Q-PCR is a fluorogenic probe-based 5’-nuclease assay that provides a higher level of specificity than conventional PCR, thus assuring the correct DNA target is amplified, and it is the preferred method to