[Indoor climate and allergy. The prevalence of allergens in Norwegian primary schools].

We have investigated the prevalence of allergens from cat, dog, house dust mite, pollen, mould and food in dust samples from schools and homes in Norway. Occurrence of cat and dog allergens in schools was surprisingly high, especially in classrooms with carpeted floors. Cat and dog-derived allergens are brought into schools through the pupils' outside contact with pets. Children who are in contact with pets at home or in their surroundings carry animal hair and dander into the classrooms on their clothes, shoes and bags. The schools seemed to be a protective environment against mite infestation, as verified by very low content of mites in both carpeted and smooth floors. Furthermore, while cat and dog allergens were more prevalent in schools than in homes without pets, mite and food allergens were more dominant in homes. Frequent cleaning is important in schools, to prevent accumulation of animal hair and dander in the classrooms. We emphasize the obvious advantages of linoleum floors over carpets in decreasing the pupils' level of exposure to indoor allergens and dust.