Scientists find low risk of parasite infection in most farmed fish species in Europe’s waters

Photo of author

By Milthon Lujan

A study showing a negligible risk of parasitic worms in four European farmed marine fish species suggests that these fish should be exempted from current EU regulations requiring freezing treatment.

Good news for European fish consumers. There is a parasite they need not worry much about in farmed fish from European mariculture. According to a study published in the journal ‘Eurosurveillance’, the risk linked to this parasite called Anisakidae is negligible in European farmed marine fish.

The rising demand for fish products in Europe and new eating trends involving the consumption of raw or undercooked fish may have increased people’s exposure to fish-borne parasites. European law therefore requires that a freezing treatment be applied to fish products intended to be eaten raw or undercooked. The only species exempted from this treatment is Atlantic salmon, which previous studies have shown to carry a negligible parasite risk. Supported by the EU-funded ParaFishControl project, the current study has therefore focused on the presence of Anisakidae zoonotic parasites – parasites that can be transmitted from animals to humans – in Europe’s most farmed marine fish species other than Atlantic salmon.

Anisakidae are a family of parasitic roundworms found in the intestines of animals. When these worms are ingested by humans consuming raw or undercooked fish, their larvae can cause a disease called anisakiasis. First identified in humans in 1960, this disease is considered a big threat to human health and is the cause of thousands of related invasive and allergic syndromes worldwide, the study reports.

Fish species studied

The researchers assessed the zoonotic Anisakidae parasite risk in gilthead seabream, European seabass, turbot and marine rainbow trout farmed in Europe’s seas. A total of 6 549 farmed marine fish were examined from March 2016 to November 2018: 2 753 gilthead seabream, 2 761 European seabass and 1 035 turbot. The samples were collected from 14 farms in Greece, Spain and Italy. A total of 200 marine rainbow trout from Denmark were also examined, in addition to 290 European seabass and 352 gilthead bream imported by Spain and Italy from Croatia, Greece and Turkey. According to the study, gilthead seabream, European seabass and turbot “represent 95% of the EU mariculture production excluding Atlantic salmon and they are farmed almost entirely in 19 Mediterranean countries, among which Greece, Spain and Italy are the most important EU producers.”

See also  Scientists establish NanDeSyn Database to support international cooperation on industrial microalgae

Given the absence of zoonotic Anisakidae worms in the fish examined, the research team found the risk of infection in the most farmed fish species produced from European mariculture activities to be negligible. The authors of the study conclude: “Farmed gilthead seabream, European seabass, turbot and marine rainbow trout should therefore be considered suitable, as Atlantic salmon, to benefit from the exemption from freezing treatment provided by EU Regulation No 1276/2011 for fish farming products in the form of ‘products intended to be consumed raw, or marinated, salted and any other treated fishery products, if the treatment is insufficient to kill the viable parasite’.”

The ParaFishControl (Advanced Tools and Research Strategies for Parasite Control in European farmed fish) project ended in March 2020. Its overall goal was to make the European aquaculture industry more sustainable and competitive. It sought to do this by improving scientific understanding of fish–parasite interactions and finding ways to prevent, control and mitigate the most harmful parasites affecting Europe’s most farmed fish species.

For more information, please see:
ParaFishControl project website 

Reference (open access):
Fioravanti Maria Letizia, Gustinelli Andrea, Rigos George, Buchmann Kurt, Caffara Monica, Pascual Santiago, Pardo Miguel Ángel. Negligible risk of zoonotic anisakid nematodes in farmed fish from European mariculture, 2016 to 2018. Euro Surveill. 2021;26(2):pii=1900717. https://doi.org/10.2807/1560-7917.ES.2021.26.2.1900717

Source: CORDIS

Leave a Comment