“What are they and how to behave”

Spring allergies are booming. As the many people who suffer from them know, every year an exploit is recorded in the months of April, May and June, even if in recent decades the period in which they are widespread has extended until late autumn.

The symptoms can involve the upper and lower airways (with problems affecting breathing, which can become labored), the eyes (they can become irritated, itchy and watery), the nose (it can close as if you had a cold and give rise to a liquid discharge) and the skin (with manifestations ranging from redness to flaking). You may also have reactions in the mouth (swelling of the lips or tongue), face and throat.

These are excessive responses by the immune system to contact with an external substance considered harmful (allergen), such as pollen, house dust mites or the fur of some animals. The severity varies from person to person and can range from mild irritation to more severe conditions: to find out more, we interviewed Dr. Fabio Maria Agostinisspecialist in Pediatrics and specialist in Allergology and Clinical Immunology.

What are the most common spring allergies?

There are many allergies that typically experience a boom in the spring period. Tracing a general overview, we can start with those concerning birch, hazel and hornbeam pollen, which are among the most widespread in the Bergamo area. Then there are those that arise from other allergens such as cypress, olive and ash, or from grasses – which constitute a very vast family of herbaceous plants – and other types of weeds such as parietaria which, as can be seen from the name , grows along the walls, in midsummer, basically in the months of July and August. Furthermore, in terms of allergic symptoms, ambrosia and absinthe are becoming increasingly popular, which are other types of herbaceous plants and are characterized by the fact that in these cases the symptoms appear at the end of summer. And in the last 20-30 years a peculiar phenomenon has been observed.

Which?

In the past, patients had mono-sensitization, that is, they were allergic to only one substance, while today this condition is a rarity. 80-90% of people have poly-sensitization, that is, they are allergic to multiple substances. In most cases they have allergies to multiple pollens and show symptoms several months during the year: they start having them between the end of December and the beginning of January – for example for hazelnut and cypress pollen – and they continue until September for ambrosia and absinthe. To this picture we must add alternaria, a mold that colonizes what is decaying or rotting. Present above all in woods and in sparsely cut grass, it is capable of reaching high concentrations in the air and in sensitized individuals it is responsible for rather significant nasal and pulmonary symptoms. It spreads its spores for three or four months, from the beginning of summer until late autumn, so it is felt for quite a long time during the year.

Considering that the symptoms are felt for such a long period of time, can we still talk about spring allergies?

Ongoing climate changes have changed the usual timing of allergy symptoms. Those relating to grasses, which in absolute terms are the most significant, record a boom in spring, in the months of April, May and June, but many pollen already circulate in winter and still others in summer and autumn. November and December are the quietest periods, unless you are sensitive to other perennial allergens such as mites or dog and cat hair: in this case, if you have these animals at home you will inevitably be constantly exposed to them .

But why do we become allergic?

More than a century ago, researchers of allergic diseases struggled to find patients to analyze their symptoms. Sensitized people were very rare, whereas today there are many. To get an idea, just think that 30-40% of adolescents suffer from it. Various reasons have an impact: genetic factors have not changed but the environment: pollution has increased and our eating habits have changed, starting with the utmost care for food hygiene, which must not have bacterial contamination. In the past our immune system had to deal with infectious diseases and less with allergies.

In what sense?

The development of better hygiene has allowed many benefits for health and more generally for society, starting with the prevention and elimination of several infectious diseases, but has also led to an increase in allergies, which for this reason are called ” diseases of rich countries”. The consumption of foods that are overly manipulated, refined and distant from the Mediterranean diet, excessive attention to cleanliness, less contact with natural environments and with infections cause the immune system to be more stimulated to produce antibodies against allergies. On the one hand there is less biodiversity and on the other a notable change in the intestinal flora resulting from excessive use of antibiotics and the consumption of junk food, which have certainly increased the risk of developing allergic diseases because they modify our intestinal microbiome. According to several studies, in fact, they have a negative effect on the intestinal barrier and promote the absorption of allergens.

But what is the difference between allergy and intolerance?

Allergies involve the immune system, while intolerances do not. And remaining in the field of allergic diseases, an increase in anaphylaxis, i.e. a form of hypersensitivity due to a special immune condition, has been found. A significant role is also played by vitamin D, which regulates our immune system and which is currently very lacking in our society.

How come?

Until fifty years ago we worked in the fields and children played outdoors, while today we spend a lot of time in the office and are less exposed to the sun, a source of vitamin D. We spend a lot in front of the computer and the TV and so we are have become a population with serious deficits of this vitamin.

And why do allergies explode in spring?

Pollens are substances that stimulate the production of Ig E – class E immunoglobulins – responsible for the symptoms in predisposed patients. Genes constitute a basic heritage, but what is of primary importance is epigenetics, that is, what regulates the expression of genes. This explains why non-allergic people gave birth to individuals who developed allergies. Children born by cesarean section, for example, have a greater risk of having allergic diseases than those born by natural birth.

Why?

The passage through the vaginal canal means that the baby is immediately exposed to the mother’s intestinal flora and will have more advantages in tolerating allergens. Breastfeeding is also an ally of the immune system, while artificial milk is less so. So, giving an example, a child who was born by cesarean section, perhaps underwent antibiotic therapies and fed with artificial milk, will be more likely to develop allergic diseases such as atopic dermatitis and food allergies.

What is atopic dermatitis?

It is an inflammatory skin disease that presents with itching and various skin manifestations such as erythema, itching and dryness. Today 30% of children contract it in the first year of life and it is the first stage of the allergic journey because it arises from the penetration of allergens into the skin. In the past it was thought that it was the consequence of an allergy, while today medicine has made progress and it has been understood that the opposite is the case. The skin barrier must remain intact to avoid contact with these allergens and all allergy societies recommend the early introduction, after the fourth month of life, of foods considered highly allergenic such as milk, eggs, fish, peanuts and hazelnuts, wheat and soy, even in the form of small tastings. The objective is to encourage the development of tolerance towards these foods through the gastrointestinal route. Alternatively, they will have a greater risk of developing allergies and sensitization occurs through the skin. And the damage to the skin barrier facilitates the onset of the allergy. Preventively, it can be helpful to maintain good hydration and use detergents that are not too aggressive, designed for the hygiene of children.

How are allergies diagnosed?

In two stages: the anamnesis – i.e. the accurate collection of data – and the execution of scientifically validated tests. The latter can be cutaneous or aimed at searching for specific Ig E in the blood. Unfortunately, today non-validated tests flourish and various national and international societies recommend not using them: there are allergist specialists.

And what can be done to treat spring allergies?

We have drugs that are increasingly effective and less burdened by side effects. We can count on therapies based on topical (local) and oral antihistamines and topical cortisone for allergic oculorinitis (inflammatory process, mostly catarrhal, affecting the conjunctiva and the mucosa of the nasal passages), while for asthma we have bronchodilators and cortisone drugs are available. The latter should not be demonized because the fear of them often causes more damage than their intake. It depends on which molecule to use and the specialist knows which ones are best to use. But we have many other weapons at our disposal.

Which?

Allergy vaccines: specific injective or sublingual immunotherapy represents an excellent remedy for controlling symptoms and improving patients’ quality of life. They constitute the only modifier of the immune response: there is no other drug capable of modifying its reactivity.

And is there any news from the research?

Yes, biological drugs, which are significantly changing the therapeutic approach. The result of the most recent pharmacological research, they use the synthesis of molecules capable of blocking the players of allergic inflammation. They have the advantage of being highly effective and essentially free of side effects, but they are still burdened by high costs, so they are currently administered in the most serious cases.

Finally, could you give some advice on how to protect yourself from these allergies?

The advice is to resort, under the guidance of specialists, to drugs with proven effectiveness to reduce the symptoms as much as possible and have an excellent quality of life.