Allergies, the “endless season” is coming. Nowadays it is possible to intervene with targeted therapies

Elena Meli

To identify allergies today, molecular tests guarantee broad-spectrum research and more effective diagnoses. Now the immune system can be gradually ‘trained’ not to respond to pollen

Every year the sneezing season starts a little earlier: climate change brings forward and even extends the difficult months for allergy sufferers. As temperatures continually rise, flowers bloom earlier, global warming increases pollen production, and therefore over the past thirty years it is estimated that the allergy season has lengthened on average by about twenty days. Another twenty days of runny nose and sneezing
a continuously growing group of people: in Europe the prevalence of
allergic rhinitis is about 23 percent, in Italy estimates are in between
16 and 25 percent, but as Giorgio Walter Canonica of the Society explains
Italian Institute of Allergology, Asthma and Clinical Immunology (SIAAIC) «according to the
According to forecasts, between 35 and 40 percent of the Italian population will suffer from this
allergic rhinitis by 2030″.

The attraction of scientists

For this reason too, a group of scientists met at the beginning of April
from around the world signed a call, published in Frontiers in Science, for mitigating the impact of climate change on diseases with an immune component: “Global warming is changing the exposome, that is, the set of environmental factors to which we are exposed. The greater incidence of extreme climatic events puts pressure on the immune system, pollution and the increase in pollen increase the likelihood that the defensive barrier of the skin and mucous membranes will be changed, the loss of biodiversity and the reduced exposure to germs due to the current lifestyle changes the balance of the immune system: the result is a greater risk of allergies, autoimmune diseases, tumors,” the experts write.

Softens the pollution

The way out, in the face of a crazy climate and a danger to human health, should be a “global effort to reduce pollution and adapt to the new conditions on the planet”, as the representatives of the most important scientific allergy associations in the world write in the recent document. It is certainly not a trivial task and as Canonica explained during a meeting dedicated to respiratory allergies of Assosalute, the National Association of Self-medication Drugs part of Federchimica: “We must face spring with crossed fingers: if the trend continues, also thanks to Considering the levels of air pollution, it will be a season with a major impact on people who are allergic.”

A multi-year season

A season that for many is becoming perpetual or almost eternal: with the lengthening of the pollination months due to higher average temperatures, those allergic to parietaria, for example, today face symptoms from February to November. However, the increase in pollen due to climate change is only part of the problem, as many factors contribute to the greater discomfort of allergy sufferers and the increase in the number of patients, as Canonica specifies: «Allergies are not hereditary, a predisposition to develop them. The problem is that the world we live in seems designed to make us allergic: today we know that the first step towards an allergy is to change the barriers that protect us from contact with the outside world, in fact the skin and epithelium (the lining of the epithelium). tissue, ed.) of the gastrointestinal tract. All kinds of pollutants to which we are exposed, from atmospheric smog to microplastics, also damage epithelium and mucous membranes and promote the entry of allergens into the body, facilitating the development of allergic sensitization. The more pollution increases, the more damage occurs to the mucous membranes, which further contributes to amplifying the abnormal immune response that leads to allergy symptoms.

The role of food

«It is not enough: even a wrong diet (for example, the ‘Western’ diet, which is becoming increasingly widespread and deviates from the Mediterranean diet by making extensive use of processed industrial foods, ed.), which changes the composition of the bacterial intestinal flora , modifies the mucous membranes of the digestive tract and in this case also promotes the passage of allergens and the occurrence of an abnormal immunological reaction. It can occur even in the elderly: allergic rhinitis can occur even at the age of 70 and it is good to be aware of this in order not to underestimate the symptoms and arrive at a correct diagnosis. The environment around us has changed a lot and now any time is a good time to become allergic,” Canonica continues. “Since the end of the pandemic, there has been an explosion of respiratory allergies, especially among young people and children, but also in adults: for a long time the mask had a protective effect against inhaling pollen, allergens, viruses and pollutants.”

A Trojan horse

As if that weren’t enough, it seems that pollen can cause symptoms even in people who are not allergic, by attaching to pollutant particles: this was shown some time ago by research from the Max Planck Institute in Mainz, Germany, where it was observed that pollen can create ozone, nitrogen dioxide and particulate matter, which are transported and released deep into the respiratory tract. “The pollen from polluted areas is covered with harmful substances that change their allergenic content and can enhance their action, making it easier to trigger allergic reactions in everyone,” said Mario Di Gioacchino, president of Siaaïc. “Nitrogen oxides and ozone, in high concentrations, alter the protein components of pollen grains to the point of causing rhinitis and cough, even in people who are not allergic: some pollens, for example those of grasses, cause the hyperactivation of cellular receptors that stimulate the immune system’s response , regardless of whether you are allergic.” In short, the panorama is bleak, if you consider that not much can be done to prevent allergies, except try to have a healthy lifestyle, spend as much time as possible in clean air and perhaps take off the mask again when we have to be forced. staying for a longer period of time where the pollution is almost “tangible”.

The bulletins

Those who are already allergic can take specific precautions, for example by consulting the updated pollen bulletins: the service is offered by many regions, otherwise you can consult the website of the atmospheric monitoring network of the Association of Italian Territorial and Hospital Allergists and immunologists. Also pay attention to the weather, because during thunderstorms or rain showers with lightning, the pollen can break and end up deeper in the respiratory tract, making the complaints more intense.

Molecular analyses

However, the first rule is that you should treat yourself well after you have been properly diagnosed. “Many still underestimate the symptoms and the importance of an in-depth evaluation, which is no longer that of simple allergy testing on the skin,” Canonica underlines. “Today, with a blood sample and extensive molecular tests, you can analyze almost 300 antigens and discover cross-allergens (for example, when the allergy to a pollen is associated with a food allergy because pollen and food share similar molecules, ed.), providing more precise indications given to protect itself from the appearance of symptoms, but above all has the opportunity to design an immunotherapy specific to the antigen that causes more discomfort than any other.

How immunotherapy works

Today, immunotherapy for pollen allergies (which consists in slowly “reaccustoming” the immune system to tolerating it by exposing itself to gradually increasing doses, ed.) is simple, it is done sublingually and has accessible costs, which in some regions are compensate. in whole or in part; above all, it can change the course of the disease because it has long-term effects, allowing tolerance to be maintained even up to five or eight years after discontinuation of treatment. This radically changes the quality of life of patients and reduces the use of other medications. Specific immunotherapy would be indicated for all people with pollen allergy in the absence of severe asthma, which should first be controlled with biologics before subsequent initiation of immunotherapy; However, it is estimated that around one in ten allergy sufferers follow it, mainly because many do not know or think it is still a matter of getting a weekly injection.” The majority therefore manage the allergy with antihistamines, sometimes with nasal decongestants, which, however, as Canonica underlines, “can cause problems in the long term. Allergies have an inflammatory basis. Therefore, the most valid therapy, especially in moderate and severe cases of allergic rhinitis, is the combination of steroids and inhaled antihistamines, which are also effective in conjunctivitis. Self-medication can be useful, but its use should always be managed with the help of the doctor,” concludes the expert.

April 20, 2024