The statistical records of foodborne diseases are scattered and thus no official records of diseases are found. The foodborne diseases cases raise every now and, for example Escherichia coli O157:H7 first described in 1983 was regarded as a rare type of food borne diseases but to date it is the major foodborne disease in industrial countries. Apart from this pathogen, other pathogens such as Salmonella, Campylobacter, E.coli, Listeria, and other pathogens are dangerous to the public health.
Bacteriophages are viruses infecting bacteria which are obligate and lack their own metabolism while phages target the host specifically and are able infect specific species or strains except some few such as Listeria phage A511 which infect and kill bacteria in the entire genus. Phages lower the incident of infection facilitating rapid detection and as a biocontrol agent. Most phages belong to caudovirales order which is isometrically headed containing double-stranded DNA. These have tail-associated proteins while the temperate phages can integrate themselves into host genome after infection. When pathogens are detected by use of phages the sensitivity of PCR may not be provided as it allows the distinction of living bacteria. It is also much more rapid than the traditional cultivation techniques.PCR assays are not applicable for routine diagnostics of a diverse range of foods.Luceferase genes have enormous advantage that background photon emission shouldn’t be present in food samples and thus luminescence reflects the presence of viable bacteria. Phage lamba vectors allow direct cloning of large DNA fragment, and are applied on a limited amount as it is a temperate phage and it has a narrow host range.
A popular detection of bacterial pathogens is the use of phage typing .This is a popular tool used to differentiate bacterial isolates and is used in epidemiological studies to identify and characterize outbreak –associated strains.
