Control of Campylobacter spp. and Yersinia enterocolitica by virulent bacteriophages

The efficacy of the Campylobacter (C.) phages NCTC12684 (group II) and CP81 (group III) and of the Yersinia (Y.) phage PY100 to reduce the numbers of Campylobacter and Y. enterocolitica in meat at 4(o)C applying different Multiplicities of Infection (MOIs) was analyzed. Initial experiments were carried out in broth at 4(o)C and 37(o)C to compare cell number reductions under chilling and optimized growth conditions, respectively. The results showed a 1 log(10) unit reduction of Campylobacter cell numbers at 37(o)C in broth. However, no reduction was observed in broth and meat at 4(o)C. In contrast, Y. enterocolitica cell numbers were reduced in broth at 4(o)C (up to 3 log(10) units after 24hr) and 37(o)C (5 log(10) units after 1.5hr) and also in meat at 4(o)C (2 log(10) units after 48hr). The highest cell number reductions were obtained at the highest MOIs.