Many farmed fish parasite-free but more data needed

These are the key findings of an EFSA scientific opinion published today, which also evaluates new methods for detecting and killing parasites in fish.

Available scientific data from the EU/EFTA area, although limited, indicates that many species of farmed fish intended for the market are free from zoonotic A term given to diseases and infections that can be transmitted between animals and humans. parasite infection. These include Atlantic salmon, rainbow trout, gilthead seabream, turbot, meagre, Atlantic halibut, carp, and European catfish.  

However, parasites like Anisakis and others were found in European seabass, Atlantic bluefin tuna, cod, and/or tench produced in open offshore cages or flow-through ponds.  

Fish produced in closed recirculating aquaculture systems with filtered water intake The amount of a substance (e.g. nutrient or chemical) that is ingested by a person or animal via the diet. and heat-treated feed are almost certainly free of zoonotic parasites.  

EFSA’s experts concluded that more data is needed to estimate the prevalence The proportion of a population found to have a condition. of specific parasites in selected fish species, farming systems, and production areas within the EU/EFTA region. This would provide a comprehensive picture of the various combinations of main farmed fish species and relevant parasites. 

Methods to detect and kill parasites 

Experts assessed new methods for detecting zoonotic parasites in fishery products. These include UV-scanning, optical, molecular and OMICs methodologies.  

They also assessed methods for the inactivation the process of rendering food parasites unable to infect humans, for example by killing them to make food safe for consumption. of these parasites. Freezing and heating remain the most efficient ways to kill them. Ongoing research is also exploring the effectiveness of various processing techniques, such as high-pressure processing, pulsed electric field, air drying, dry-salting, double salting, and use of natural products.  

Next steps

EFSA's experts will determine by the year's end whether any wild fish species from specific fishing areas pose a risk to public health due to the presence of zoonotic parasites.