International Journal of Science & Technology ISSN (online): 2250-141X www.ijst.co.in Vol. 2 Issue 1, February 2012 © Copyright – IJST 2011 36 PRESENCE OF LISTERIA SPP. IN ICE CREAM AND SEWAGE WATER PARTICULARLY LISTERIA MONOCYTOGENES AND ITS PATHOGENECITY Bikash Kanti Biswas (Scientist) and Sourav Chandra (Asstt. Director, Extension) Directorate of Research, Extension and Farms, West Bengal University of Animal and Fishery Sciences, Kolkata, West Bengal, India drsouravchandra1@yahoo.com Abstract A total of 60 branded Ice cream samples and 90 non branded Ice cream samples were tested for presence of Listeria spp.. It was found that both types of samples were positive for Listeria spp. and also L. monocytogenes. 12% of branded and 9% of non branded ice cream samples were contaminated with Listeria spp.. Among positive samples L. monocytogenes was detected in 29% and 13% of samples respectively. Listeria spp. was much higher in branded ice cream samples than that in non-branded one. Out of a total 20 and 30 sewage water samples collected from industrial and domestic areas 15% and 30% were positive for Listeria spp. samples respectively but no sample was positive to L. monocytogenes. Pathogenecity was tested in rabbit model and the organisms were re-isolated from test dead rabbit. The histopathological changes find in the experimental rabbits were typical one. It may be concluded from these observations that the zoonotically important as well as highly pathogenic Listeria species are present in the sewage water in and around Kolkata, West Bengal, India. Key Words: Listeria, ice cream, sewage water, Kolkata 1. Introduction Listeria monocytogenes is the most important species in the genus Listeria creating human and animal health hazards and having a worldwide distribution with an extensive host range. Listeria spp. can grow well in complex media at a wide range of temperature (3 o to 42 o C) (Seeliger & Jones, 1986). It affects primarily pregnant patients, neonates, elderly and immunocompromised individuals. Its significant role as food borne human pathogen became evident only in 1980s (Schlech et al. 1983). The manifestations of the disease in animals include localized encephalitis or meningoencephalitis, a generalized septicaemia form of infection with hepatic necrosis, abortion in mammals and myocardial degeneration in fowls (Hird and Genigeorgis, 1990). Emergence of human food borne listeriosis as a major public health concern is major attributed to intensification in food production, processing and distribution, increased use of refrigeration as a primary means of preservation for food, change in the eating habits of people, particularly towards convenience and ready- to- eat foods (Swaminathan, 2001). Presence of Listeria spp. as well as L. monocytogenes in beef collected from Kolkata city and surrounding areas was observed by Biswas, 2010. Considering zoonotic importance of Listeria spp. particularly L. monocytogenes and scanty knowledge on the existence of different Listeria spp. in environment in Kolkata, the present study to enumerate the prevalence of Listeria spp. in ice cream and city sewages