Pollens return with spring and sunny days. And allergy sufferers will again be embarrassed. What is desensitization and how is it effective?
- Pollens, among other things, are allergenic.
- In France, 15 to 20% of people aged 15 to 70 are affected.
- It is possible to practice desensitization in order to considerably reduce the symptoms.
Pollen, mainly birch in this season, will continue to disturb allergy sufferers over the next few days. THE National Aerobiological Monitoring Network (RNSA) publishes a daily bulletin which makes it possible to follow the level of risk according to the regions. “People allergic to birch pollen should be on their guard and follow the treatments prescribed by doctors.” Desensitization may be necessary.
What is desensitization?
Desensitization allows the body to be gradually exposed to the allergen so that the immune system can tolerate it. At an allergist, allergic patients perform skin tests with different allergens to determine the origin of allergies (birch pollen, grass pollen, cat or dog hair, dust mites, etc.). These tests can be accompanied by a possible blood test or a consultation with a pulmonologist. Based on the results, the doctor can decide if the patient is a good candidate for desensitization. If this is the case, the allergens will be gradually injected into the patient’s body through tablets or drops. The efficiency of these two processes is the same. In the case of severe allergies, the treatment takes place by injections with a doctor or in the hospital.
Desensitization is recommended three to four months before pollen season and for at least four months, as the introduction of allergens into the body will become increasingly important over time. It should be noted that one can be desensitized from the age of 5, but not in the event of a food allergy, multiple allergies or even if the person suffers from an autoimmune disease or cancer. Overall, desensitization can significantly reduce allergy symptoms, such as fatigue, colds, headaches, or asthma attacks.
A real public health problem
Today, allergies have become a real public health problem, directly linked to environmental changes and new lifestyles. The National Institute of Health and Medicine (Inserm) estimates that “25 to 30% of the population is allergic“. According to the World Health Organization (WHO), this proportion should reach 50% by 2050. In France, 15% to 20% of people aged 15 to 70 are affected.
It is important not to deny the weight represented by allergies in daily life: fatigue, absenteeism from school, reduced productivity at work, etc.
Why is pollen allergenic?
Austrian researchers have explained the origin of pollen allergies in the Journal of Biological Chemistry in 2014. They reproduced the birch pollen allergen in the laboratory: the Bet v 1 protein (Betula verrucosa). This makes the immune system hypersensitive and leads to the formation of pathogenic antibodies in 95% of allergy sufferers. The researchers found that the molecular “pockets” of the Bet v 1 protein determine whether pollen will be allergenic.
To be more precise, Bet v 1 can, thanks to the molecular pockets, bind to iron. If these pockets remain empty, the pollen turns into an allergen, as it manipulates the Th3 immune cells to make them react. In allergy sufferers, scientists have highlighted an imbalance between Th3 cells, which protect the body from allergies and parasites, and Th1 cells, which respond to bacterial infections.
