Shellfish allergy usually appears in adulthood and lasts a lifetime, so to prevent it, it is essential to avoid consumption or contact with these foods after a first allergic reaction.
The shellfish are marine invertebrates which, together with fish, one of the highest numbers of food allergies originates. Among the shellfish, the most allergic are crustaceans (prawn, lobster, Norway lobster, lobster, spider crab, crab), followed by mollusks, especially shell clams, mussels, cockles, and oysters.
Having an allergy to shellfish does not necessarily mean having an allergy to fish because they are different foods. However, more and more cross-reactions are being detected, and it has been found that those allergic to shellfish often have allergic reactions to dust mites. Both animals have a similar protein in the muscle, which is responsible for the allergic reaction.
As with other types of allergies, the fact that you have consumed and tolerated shellfish in the past does not mean that you cannot have an allergic reaction later. In fact, a shellfish allergy often appears in adulthood and usually persists for life. The allergy usually occurs when ingesting shellfish, but allergic reactions have also been observed in people who have handled the meat or inhaled the vapor from shellfish.
It should be noted that most people who are allergic to fish are atopic, and severe reactions are more common in them.
Shellfish contain a great diversity of proteins, although only a few are allergenic. It is essential to bear in mind that allergens are water-soluble glycoproteins that are not destroyed in the cooking process so that cooked seafood maintains its allergenic properties, as does the water in which it has been cooked.
Although a person can be allergic to a single shellfish, such as prawns, Experts warn that there is a high percentage of cross-reactivity between different species of shellfish (in some cases it exceeds 85%). therefore, they recommend that the person who has already had an allergic reaction to one type of shellfish, avoid consuming the others as a precaution.
Prevalence of shellfish allergy
The exact prevalence of this allergy is unknown. However, it is related to the eating habits of the population, which is why it is more frequent among people who include shellfish in their usual diet, such as residents of coastal towns. However, the consumption of shellfish has become widespread in recent years, which has increased the number of adverse reactions among consumers and handlers of this food.
Symptoms of shellfish allergy
The symptoms of an allergic reaction to shellfish are similar to those of other food allergies and include hives and acute angioedema (swelling), especially on the face, eyelids, lips, and tongue. When handling this food, allergy sufferers develop contact dermatitis and urticaria, which manifest with itching, the appearance of small blisters or hives, and scaling and redness of the affected area hands.
Symptoms generally appear between 15 minutes and two hours after ingestion and, exceptionally, several hours after consuming the food.
Symptoms of shellfish allergy can appear simply by inhaling the fumes that are produced during cooking or the particles that are released when handling, in the form of rhinitis and asthma. This type of respiratory sensitization, which precedes food allergy manifestations, is responsible for occupational asthma.
Some food industry workers dedicated to handling shellfish have developed an allergy to it, presenting contact dermatitis, urticaria, and occupational asthma.
Some factors accelerate the allergic reaction to shellfish, such as when the ingestion of the food coincides with the taking of anti-inflammatory drugs or the practice of physical exercise.
It is important to detect the allergy as soon as possible to avoid an anaphylactic reaction, a severe and very rapid allergic manifestation that affects the whole body. That occurs when a person allergic to a substance is exposed to it again (although it is small). Anaphylaxis can lead to breathing difficulties, loss of consciousness, and even death.