Eating fish is a healthy habit, but it can have consequences on human health, namely the danger of parasite infection if the fish is consumed raw or undercooked.
A team composed of researchers from the Laboratory of Animal Pathology of the Interdisciplinary Center for Marine and Environmental Research (CIIMAR) and the Department of Biology of the Faculty of Sciences of the University of Porto (FCUP), published recently an article in the scientific journal food controlpublished by ELSEVIER, in which he alerts to the dangers associated with eating raw fish.
Currently, Portugal continues to be one of the largest consumers of fish worldwide, with an average annual consumption of 60 kg per inhabitant, compared to an average of 27 kg per inhabitant in the European Union.
However, this healthy habit may have health consequences human, in particular danger of parasite infection if the fish is eaten raw or undercooked.
THE anisakiosis is an example of a disease caused by eating raw fish. Caused by the parasite Anisakisis more frequent in Asian countries, particularly Japan, and in European and South American fishing communities.
The most frequent clinical manifestations are gastric disorders caused by infection with the larva, or allergic reactions to chemicals released by the parasite in the fish.
“It is very important to know better the situation of the infection by Anisakis of Portuguese commercial fish, where unfortunately not much has been invested in its financing to date”, he points out. Maria Joao Santosleader of the research group on Animal Pathology at CIIMAR and one of the three authors of the work.
The FCUP researcher also warns that “the grilled fish, if not properly cooked, can also be dangerous”. In this sense, “the best thing will always be to bet on infection prevention methods and always freeze the fish consumed raw for the necessary time”.
Photo: Maria Joao Santos
The Anisakis parasite is responsible for anisakiosis, a disease caused by eating raw fish.
Recommendations for consumption of raw fish
At five most consumed species of fish raw in Portugal are salmon, tuna, cod, hake and sardines. And they all deserve special care, according to U.Porto researchers
For those who appreciate sushi, sashimi, or marinated fish, there are certain precautions that must be taken into account to avoid infections, namely freezing at -20ºC during the 24 hours before consumption. If applied correctly, this method can kill the parasite, although it does not avoid the problem of allergens.
THE salmon, for examplebeing aquaculture fish, it will not have these worms, but if it is wild fish may be heavily parasitized. In that case, it needs to be frozen before being eaten raw.
In case of codsalting is also a method that prevents worms, so it will be safe to eat properly salted cod.
THE hake it is heavily parasitized and must always be frozen. Sardines, on the other hand, have shown low levels of infection, while information on the tuna situation is lacking.
Given the volume and species of raw fish consumed in Portugal, anisakiosis still represents a limited risk for the Portuguese population.
Nonetheless, infections are on the rise with the increase in consumption in recent years, and communicating about this risk becomes increasingly necessary among the Portuguese population.
Thus, the study draws attention to the need to focus on publicizing the problems related to the consumption of raw fish to the general public, and to inform consumers about the care to freeze all fish consumed raw or undercooked.
