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The control of shigellosis in humans enjoys a prominent position in the history of bacteriophage therapy. d'Herelle first demonstrated the efficacy of phage therapy by curing 4 patients of shigellosis, and several subsequent studies confirmed the ability of phages to reduce Shigella based infection. Shigella spp continue to cause millions of illnesses and deaths each year and the use of phages to control the disease in humans and the spread of the bacteria within food and water could point the way forward to the effective management of an infectious disease with global influence.

There has been much recent interest in the use of phages as biocontrol agents of foodborne pathogens in animals used for food production, and in the food products themselves. This interest seems to be driven by consumers' request for more natural foods, as well as the fact that foodborne outbreaks continue to occur, globally, in many foods, some of which (such as fresh produce), lack adequate methods to control any pathogenic contamination present. Also, the many successes with respect to regulatory approval of phage based products destined for use in foods is leading to an increase in the number of phage products that are commercially available. At present, these products are directed against three main foodborne pathogens including Escherichia coli O157:H7, Salmonella spp and Listeria monocytogenes. In the future, it is likely that new phage products will be targeted against emerging foodborne pathogens. Here, we review the current literature and status of phage based strategies aimed at reducing the presence of foodborne pathogenic bacteria in food and the food production environment.

Most diagnostic approaches for Shiga toxin producing Escherichia coli (STEC) have been designed to detect only serogroup O157 that causes a majority, but not all STEC related outbreaks in the United States. Therefore, there is a need to develop methodology that would enable the detection of other STEC serogroups that cause disease. Three bacteriophages (phages) that infect STEC serogroups O26, O103, O111, O145 and O157 were chemically labeled with horseradish peroxidase (HRP). The enzyme-labeled phages (Phazymes) were individually combined with a sampling device (a swab), STEC serogroup-specific immunomagnetic separation (IMS) beads, bacterial enrichment broth and luminescent HRP substrate, in a self-contained test device, while luminescence was measured in a hand-held luminometer.The O26 and O157 Phazyme assays correctly identified more than 93% of the bacteria tested during this study, the O123 Phazyme assay identified 89.6%, while the O111 and O145 Phazyme assays correctly detected 82.4% and 75.9%, respectively. The decreased specificity of the O111 and O145 assays was related to the broad host ranges of the phages used in both assays. The Phazyme assays were capable of directly detecting between 10(5) and 10(6) CFU/ml in pure culture, depending on the serogroup. In food trials, the O157 Phazyme assay was able to detect E. coli O157:H7 in spinach consistently at levels of 1 CFU/g and occasionally at levels of 0.1 CFU/g. The assay detected 10(0) CFU/100 cm(2) on swabbed meat samples and 10(2) CFU/100 ml in water samples. The Phazyme assay effectively detects most STEC in a simple and rapid manner, with minimal need for instrumentation to interpret the test result.