Climate change, air pollution, and increase of respiratory allergies: just a coincidence or something more?

It is well known that the prevalence of respiratory allergies has increased over time. At the same time, climate change has become part of our everyday life. The resulting question is whether this 'allergic epidemic' is linked to this aspect. It is assumed that the causes of the increase of respiratory allergies are mainly related to environmental factors and lifestyle: first, the improvement of social and health conditions and related hygiene hypothesis; secondly, lifestyle change and anthropogenic activities, which have caused an alteration in the balance normally existing between soil, water, and atmosphere, giving rise to the phenomena of climate change. In fact, it has been demonstrated that they can influence beginning, duration, and intensity of the pollen season, as well as the allergenicity of pollen. The consequence is both an increase in frequency and intensity of allergic symptomatology in subjects previously affected by allergy, and a promotion of the sensitization of the airways to allergens present in the atmosphere in predisposed subjects. Several intervention strategies aiming to mitigate climate change and reduce anthropogenic emissions and, consequently, respiratory allergies are possible and can be implemented on an individual and social level. It follows that the allergist cannot solve the problem of the progressive increase of respiratory allergies on his own. Anyway, his role can have both clinical and educational purposes with a special commitment to reduce health impact due to environmental risk factors.