He fish is a very healthy food which brings multiple benefits to our body, so it should not be missing in the diet of children or during pregnancy. However, we must pay attention to the type of fish we consume (some have high mercury content), as well as the way they are cooked and preserved as they could transmit anisakis.
According to the latest data the number of allergic reactions by anisakis has increased in recent years, and although it is not a typical allergy among children, it is important to know how we can prevent it and what to do if we come into contact with this dreaded parasite.
What is anisakis?
Anisakis is a worm-shaped parasite that lives in the digestive tract of fish, cephalopods and marine mammals. It is usually between three and five centimeters long, and its color is whitish, almost transparent.
This parasite can become a problem for man at the moment when becomes part of the food chain through the consumption of infested fish and cephalopods, although in the majority of the occasions it does not cause damages in the human being.
Where is the anisakis?
Anisakis larvae are found in the abdominal cavity of between 40 and 80 percent of the marine fish and cephalopods of all the seas and oceans of the world:
In the fish that we usually consume, such as hake, sardine, herring, turbot, mackerel, salmon, anchovy, tuna, whiting and cod.
In cephalopods, such as sepia, squid and octopus.
Anisakis does not parasitize bivalve molluscs (mussels, oysters, cockles, clams), shellfish shellfish (shrimp, shrimp, shrimp, lobster, crab), or river fish (such as trout or carp).
As for the farmed fish There is a mistaken belief that they are free of anisakis, but the truth is that it is difficult to be able to affirm it emphatically, and in some cases these fish could also house the parasite inside them if they have been fed with infested species.
What symptoms does anisakis allergy produce?
The first thing to note is that the Anisakis allergy should not be confused with fish allergyWell, they are totally different things.
The most common is that most of us have ingested larvae of anisakis present in the fish we consume without this fact has caused us any alteration or complication of health.
It is estimated that 16 percent of the population has positive anisakis allergy tests, but no allergy symptoms.However, on other occasions the intake of anisakis can have the following consequences:
Anisakis or anisakiasis infection: occurs when live larvae penetrate our digestive tract, adhering to the mucosa and causing symptoms such as severe gut pain a few minutes or days after consuming infested fish, vomiting, diarrhea and even digestive bleeding.
Anisakis allergy: This live or dead parasite can cause an allergic condition that occurs in different forms, such as hives (itching and hives on the skin), allergic rhinoconjunctivitis (itchy nose and eyes, sneezing and conjunctivitis), asthmatic crisis and, less frequently, anaphylactic reaction
How is it diagnosed?
Though Anisakis allergy was an exceptionally rare thing a few decades ago, now more and more cases are diagnosed, being very frequent in Japan and, within Europe more prevalent in our country, in France, in Holland and in Germany.
The diagnosis of allergy should be made by the specialist, through the patient's medical history and the results of specific tests.According to Dr. Pilar Cots, allergist at the Ruber Hospital and author of the blog Not without my allergy, the way to determine if there is an allergy to anisakis is by skin test (or prick test) and analytical to determine the levels of specific IgE in blood. Sometimes it may also be necessary to perform a endoscopy to detect and remove larvae.
How does anisakis allergy affect children and pregnant women?
According to experts, unlike other conventional food allergies, anisakis allergy usually occurs unexpectedly in adults between 40 and 70 who have no allergic history.
In this article published in Pediatric Web we can read how to not be a common allergy among the child population, pediatricians find it difficult to diagnose it quickly, and the first thing they tend to think about is that they are faced with some of the most frequent allergies in children, such as allergy to milk, egg, fish, fruit or legumes.
But once these possibilities have been ruled out, and depending on the time that has elapsed between the fish intake by the child and the appearance of symptoms, it is possible that the specialist begins to have suspicions of being faced with a case of anisakis allergy.
As for pregnant women, it is important to exercise caution when eating fish, since precisely This allergy can be avoided with appropriate preventive measures.
In most occasions, the treatment will be symptomatic and will consist of antacids, antihistamines and corticosteroids to mitigate allergic reactions. If they are serious reactions, the use of injectable adrenaline will be required. All this, always guided and prescribed by a specialist doctor.
In cases where anisakis is causing serious health problems, it will be necessary to remove it from the intestinal mucosa through an endoscopy. Do not suppress the intake of fish and cephalopods, but consume them according to security measures that we explain below.
Preventive measures to prevent contagion
The most effective measure to kill anisakis larvae and prevent contagion is buying frozen fish (deep-sea deep freezing) or freezing it at home for a minimum of 72 hours at -20º. Thus, Once defrosted we can prepare or consume the fish as we like: undercooked, raw, pickled ...
If we buy fresh fish and we don't want or we can freeze it, we must follow the following preventive measures:
Cook it at 60º for at least two minutes, making sure that it is very done inside and avoiding culinary techniques such as the iron or the microwave.
Do not consume raw or processed fish with the following techniques: smoked, pickled, pickled, marinated, carpaccios, sushi ...
Ask the fish shop to clean the fish well and remove the viscera, or choose the part of the fish furthest from its abdominal area (for example, the tail).
Do not consume small fish with viscera, such as sardines or anchovies.
Photos | iStock
