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Abstract Listeria monocytogenes has been recognized for many years as a facultative pathogenic bacterium that causes serious illness in animals and man called listeriosis, it appears to be commonly present in raw and ready-toeat foods. The present study was undertaken to determine the incidence and distribution of Listeria spp. in poultry and some food samples and to investigate listeriosis in pregnant women and their newborns. Genotyping of L. monocytogenes isolates were determined to detect inlA gene as a target by using polymerase chain reaction. 400 samples comprising, poultry (100), chicken pâté (50), hen’s egg (100), fish (100) and smoked herring (50) were collected from different poultry slaughter houses, shops, supermarkets and fish markets in Assiut province, Egypt. The study also, included 25 women suffered from intrauterine fetal death, 25 premature labored women and their 25 newborns admitted to Special Care Baby Unit (SCBU), Assiut University Hospital. The overall incidence of Listeria spp., L. monocytogenes, L. innocua, L. ivanovii, L. welshimeri, L. seeligeri and L. grayi was 81 (17.05%), 15 (3.15%), 40 (8.42%), 4 (0.84%), 11 (2.7%), 10 (2.1%) and 1 (0.21%), respectively, of the all examined samples. In this study, the warm enrichment method was compared with the cold enrichment for isolating Listeria species, 75 (15.79%) and 70 (14.74%) out of the examined 475 were positive as determined by warm and cold enrichment methods, respectively and no significant difference was found between the two methods. The study revealed that 10%, 20% and 57% of poultry, hen’s egg shell and fish samples were contaminated with Listeria spp., respectively and Listeria was not detected in chicken pâté, egg contents and smoked herring samples. Listeria spp. isolated from 25 poultry wings (meat and skin) in a rate of 12% including, L. innocua (4%), L. welshimeri (4%) and L. seeligeri (4%). Out of 25 poultry legs examined in this study, Listeria spp. was isolated from 12% including, L. innocua (4%), L. welshimeri (4%) and L. seeligeri (4%). Among 50 poultry intestine examined in this study, Listeria spp. was isolated from 8% including, L. monocytogenes (4%), L.welshimeri (2%) and L.seeligeri (2%). Out of 50 egg shell examined in this study, Listeria spp. was isolated from 20% including, 8%, 6%, 2% and 4% L. monocytogenes, L. innocua, L. ivanovii and L. seeligeri, respectively. The incidence of Listeria species in Clarias anguillaris slime and Tilapia nilotica slime was 80% and 60%, respectively. Concerning the distribution of Listeria spp. in the examined samples of Tilapia nilotica slime; out of the 25 samples examined in this study, 8%, 28%, 4%, 8%, 8% and 4% of the examined samples were contaminated with L. monocytogenes, L. innocua, L. ivanovii, L. welshimeri, L. seeligeri and L. grayi, respectively. While, 16%, 40%, 8%, 8% and 8% of the examined Clarias anguillaris slime samples were contaminated with L. monocytogenes, L. innocua, L. ivanovii, L. welshimeri and L. seeligeri, respectively. The incidence of Listeria species in Clarias anguillaris and Tilapia nilotica intestine was 68% and 20%, respectively. Only L. innocua and L. welshimeri were isolated from Tilapia nilotica intestine in a rate of 12% and 8%, respectively. While, 4%, 52%, 8% and 4% of the examined Clarias anguillaris intestine were contaminated with L. monocytogenes, L. innocua, L. welshimeri and L. seeligeri, respectively. The incidence of human listeriosis was 5.3%. Regarding women examined in this study, L. monocytogenes was isolated from 1 (2%) of the examined vaginal swabs of a woman at 2nd pregnancy, aged 25 year, suffered preterm labor for the first time. L. innocua was isolated from 2 (4%) out of the examined 50 vaginal swabs, both cases were women at 3rd pregnancy, suffered of intrauterine fetal death for the first time, one of them aged 32 year. While, the other aged 29 year. It was found that all positive cases, in this study, were women coming from rural areas. Out of 25 examined neonatal blood samples only 1(4%), newborn of a woman at 2nd pregnancy, aged 25 year, suffered preterm labor for the first time proved to be infected with L. monocytogenes Out of 15 L. monocytogenes isolates detected, 6 (40%) were found to harbor inlA gene and considered to be virulent strains. The existence of Listeria species and L. monocytogenes in the examined food samples, warrants the need for appropriate control measures as this would pose a serious threat to human health. |