School as a risk environment for children allergic to cats and a site for transfer of cat allergen to homes

Background: Many children are allergic to furred pets and avoid direct pet contact. The school may be a site of indirect exposure to pet allergens, wh ich may induce or maintain symptoms of allergic diseases. Objective: We sought to investigate airborne levels of cat allergen (Fel d 1) at schools and in homes with or without cats and to study clothes as a r oute for dissemination of allergens between homes and school. Methods: Airborne fat allergen was collected with personal samplers from (1 ) children attending classes with many >25%) or few (<10%) cat owners and ( 2) homes with or without eats. A recently developed amplified ELISA assay, which detects low levels of airborne cat allergen in pet-free environments, was used. Dust samples were collected from clothes and mattresses. Results: There was a 5-fold difference in the median levels of airborne cat allergen between classes with many and few eat owners (2.94 vs 0.59 ng/m(3 ); P < .001). The median airborne cat allergen concentration in classes wit h many cat owners was significantly higher than that found in the homes of non-fat owners (P < .001) but lower than that found in homes with eats (P < .001). Allergen levels in non-cat owners' clothes increased after a school day (P < .001), Non-cat owners in classes with many cat owners had higher levels of mattress-bound cat allergen (P = .01). Conclusion: The results indicate significant exposure to fat allergen at sc hool, Allergen is spread through clothing from homes with cats to classroom s. There the allergen is dispersed in air and contaminates the clothes of c hildren without cats. The allergen levels in non-cat owners' homes correlat e with exposure to cat allergen at school.