ZOONOTIC HELMINTHS IN LACUSTRINE FISH FROM NORTHERN ITALY

According to EFSA Scientific Opinion on risk assessment of parasites in fishery products issued in 2010, all wild fish should be considered at risk of containing any viable zoonotic parasites if eaten raw or almost raw, pointing out the need to carry out epidemiological surveys on presence/diffusion of zoonotic parasites in all fishery grounds. With this regard, in the framework of a research project (RF-2010-2311360) financed by the Italian Ministry of Health, a parasitological survey aimed at assessing qualitative and quantitative data on zoonotic helminths in commercially important fish caught in lakes (Maggiore, Como, Iseo, Garda) from northern Italy has been carried out from March 2013 to December 2014. Concerning Diphyllobothriid plerocercoids, abdominal cavity and fillets of 2216 fish (1820 perch, 172 shad, 104 whitefish, 92 burbot and 28 pike) were examined by visual inspection. Diphyllobothrium latum plerocercoids were found in perch (Maggiore 6.6%; Como 25.4%; Iseo 7.8%), pike (Maggiore 100%; Como 84.2%; Iseo 71.4%) and burbot (Como 3.6%; Iseo 3.8%), while shad and whitefish were negative. All the fish from Garda Lake were negative. Moreover, 239 cyprinids were analyzed for Opisthorchis felineus metacercariae by microscopical examination of compressed/digested muscular tissue. All the cyprinids were negative for O. felineus, while metacercariae of the Opisthorchiid Pseudamphistomum truncatum were detected in 2 tench and 1 rud from Como Lake. These data confirm D. latum as the most important fish-borne zoonotic helminth in the areas under study and identify the consumption of raw perch (“perch carpaccio”) as the main source of infection.