[Outdoor and indoor allergens and the respiratory tract]

This paper gives an overview of common outdoor and indoor allergens which cause sensitisation of the respiratory tract and considers relevant biological and ecological hallmarks and symptoms of allergies. Grass, tree, and weed pollens as well as moulds (Cladosporium and Alternaria species) are a major source of allergens in the outdoor environment whereas mites (Pyroglyphidae, Acaridae, and Glycyphagidae), animals (pets, rodents, and insects), and moulds (Aspergillus, Penicillium, and Mucor species) are a major source in the indoor environment. The paper pays attention to the seasonal, geographical, and climatic influence on the concentration of allergen in the environment. The authors discuss differences between exposure to outdoor and indoor allergens, as well as the impact of pollutants on sensitisation of the respiratory tract. The paper proceeds with a short description of the primary prevention measures such as avoidance of the allergens and the secondary measures which are intended to prevent the occurrence or deterioration of respiratory symptoms in sensitised persons.