FOOD MICROBIOLOGY www.elsevier.nl/locate/jnlabr/yfmic Food Microbiology 22 (2005) 133–137 Short Communication Prevalence of Aeromonas hydrophila in fish and prawns from the seafood market of Coimbatore, South India G. Vivekanandhan a, *, A.A.M. Hatha b , P. Lakshmanaperumalsamy c a Laboratory of Fish Health Management, Tokyo University of Marine Science and Technology, 4-5-7, Kounan, Minato-ku, Tokyo 108-8477, Japan b Department of Biology, School of Pure and Applied Sciences, The University of the South Pacific, P.O. Box 1168, Suva, Fiji c Department of Environmental Sciences, Bharathiar University, Coimbatore 641 046, Tamil Nadu, India Received 3 September 2003; accepted 26 January 2004 Abstract Five hundred and thirty six samples of fishes and 278 prawn samples from the major fish market of Coimbatore, South India, were analysed for the prevalence of Aeromonas hydrophila over a period of 2 years (June 1997–May 1999). The prevalence level of A. hydrophila varied from 17.62% in prawns to 33.58% in fishes. More than 30% of the popular table fishes such as Sardinella longiceps, Rastrelliger kanagurta, Mugil cephalus and Caranx sexfasciatus were tested positive for this organism. Among the different species of the prawns analysed, Penaeus semisulcatus showed higher incidence (23.52%). Seasonal variation in the prevalence levels of A. hydrophila in fish and prawns revealed a higher prevalence during the monsoon season during 1997–98 and 1998–99. Of the different body parts of the fishes analysed for A. hydrophila, the intestinal samples showed higher prevalence (38.43%), followed by body surface (32.46%) and gill (29.10%). Considering the psychrotrophic nature and role of A. hydrophila as a pathogen of emerging importance, the considerably high levels of this organism in a popular food item such as fish and prawn raises serious concern. r 2004 Elsevier Ltd. All rights reserved. Keywords: Aeromonas hydrophila; Fish; Prawn 1. Introduction Aeromonas spp. represents a group of ubiquitous micro-organisms of aquatic environments such as fresh water, coastal water and sewage (Monfort and Baleux, 1990). These bacteria have a broad host range and have often been isolated from humans with diarrhoea (Ash- down and Koehler, 1993; Janda and Abbott, 1998), though they are recognized as primary pathogens to a wide range of cold blooded animals, in particular to fish (Austin and Adams, 1996). Strains isolated from the environment do not seem to differ from strains isolated from cases of infection with respect to the prevalence of virulence factors (Krovacek et al., 1994). However, it has been reported that certain species are more frequently isolated from patients with diarrhoea as well as from diseased fish than from the environment (Kirov et al., 1994). A variety of foods have been shown to harbour motile aeromonads including seafoods (Abeyta and Wekell, 1988), raw milk, sausage (Buchanan and Palumbo, 1985) chicken, fresh beef and pork (Okrend et al., 1987), lamb and meat offal (Majeed et al., 1989). Hudson and Delacy (1991) have examined the incidence of motile aeromonads in a variety of uncooked and ready to eat foods. Coimbatore is a cosmopolitan, land locked city in Tamil Nadu, South India. Fishes and prawns are popular food item and the consumption is steadily increasing owing to their nutritional value and afford- ability when compared to other foods of animal origin. The demand for fish is met by the fishes transported from neighbouring coastal states such as Kerala and Andhra Pradesh as well as from the distant coastal city of Rameswaram in Tamil Nadu. Aeromonas spp. being ubiquitous in the aquatic environment has been reported from wild fish, pond cultured edible and ornamental fish ARTICLE IN PRESS *Corresponding author. Tel./fax: +81-3-5463-4054. E-mail addresses: aerovivek@hotmail.com (G. Vivekanandhan), abdulla m@usp.ac.fj (A.A.M. Hatha), lps@mailcity.com (P. Lakshmanaperumalsamy). 0740-0020/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.fm.2004.01.015