Genetic Characterization and Antibiogram Profiles of Listeria Species Isolated from Poultry and Poultry Handlers

Up to now, there has been limited information regarding the circulation of pathogenic Listeria species in poultry and their contact handlers. The present study was, therefore, planned to evaluate the potential existence of Listeria spp. in different poultry species and their products as well as their contact workers at Dakahlia Governorate, Egypt and to address the antimicrobial profile of Listeria isolates using classical microbiological techniques and multiplex PCR targeting three virulence-associated genes (iap, hlyA, and actA). The study included cloacal swabs from different poultry species (n =200), poultry carcasses (n = 25), poultry products (25 samples each of chicken luncheon and frozen chicken breast fillets), chicken eggs (n = 50) and stool specimens from the contact workers (n = 25). Findings showed that 60 samples out of 350 (17.14%) were found to be positive to Listeria spp., which were identified as follow: L. innocua (28.3%), L. ivanovii (28.3%), L. monocytogenes (15%) and L. grayi (15%), L. seeligeri (10%) and L. welshimeri (3.3%). L. monocytogenes showed high resistance to nalidixic acid (100%) followed by neomycin (85.1%), streptomycin (80%), cefotaxime (65%) and penicillin g (58.3%). Results could likely suggest that poultry and poultry products had a significant role in dissemination and transmission of virulent and multidrug resistant L. monocytogenes which represent a potential risk particularly in the absence of strict hygienic practices and preventive measures. A constant monitoring of pathogenic L. monocytogenes is thus urgently needed to avoid the dissemination of such pathogenic strains in food production chains.