Introduction: Several zoonotic helminths can be transmitted to humans by consumption of
raw, undercooked, marinated or cold smoked fish products, representing a relevant public
health concern. Although up to now in Italy the presence of zoonotic helminths has been
documented only in wild fish populations, extensive epidemiological surveys are needed in
order to assess the possible zoonotic risks linked to consumption of national aquaculture
products. At this purpose, a wide parasitological survey has being undertaken on rainbow
trout Oncorhynchus mykiss (RBT), gilthead seabream Sparus aurata (GSB) and European
seabass Dicentrarchus labrax (ESB) farmed in Italy.
Methodology: From spring 2016 to spring 2017 a total of 2347 fish have been examined. In
particular, 738 RBT from 4 Italian freshwater trout farms (two farms located in the area
endemic for diphyllobothriasis in Northwestern Italy, 1 in the area endemic for
opisthorchiasis in Central Italy and 1 in a highly productive area of Northeastern Italy) were
subjected to methods aimed to search for larval stages of diphyllobothriid cestodes (visual
inspection and candling) and opisthorchiid digeneans (muscular compression/artificial
digestion followed by microscopic examination). Furthermore, 781 GSB and 828 ESB from 4
marine farms (3 cage systems and 1 inland farm located in Tyrrhenian and Adriatic seas)
were examined for anisakid larvae by UV-press method and artificial digestion. A seasonal
periodicity has been applied, sampling 65 specimens/fish species/farm/season in order to
reach a statistically significant amount of fish at the end of the survey (258 fish/farm).
Results: No zoonotic parasites have been found in all the examined fish at the level of
confidence of 99% with a margin of error of 5%.
Conclusions: The results so far obtained during this survey are encouraging and seem to
confirm that the risks linked to zoonotic helminths in Italian aquacultured fish species are null
or negligible, when good farming practices are applied along the production chain