S. Parvaneh M. Kronqvist E. Johansson M. van Hage-Hamsten Authors' af®liations: S. Parvaneh, M. Kronqvist, E. Johansson, M. van Hage-Hamsten, Department of Laboratory Medicine, Division of Clinical Immunology, Karolinska Institute and Hospital, Stockholm M. Kronqvist, Department of Medicine, Danderyd Hospital, Danderyd, Sweden Correspondence to: Shahram Parvaneh, BSc Division of Clinical Immunology Karolinska Hospital S-171 76 Stockholm Sweden Date: Accepted for publication 24 September 1998 To cite this article: Parvaneh S., Kronqvist M., Johansson E. & van Hage- Hamsten M. Exposure to an abundance of cat (Fel d 1) and dog (Can f 1) allergens in Swedish farming households. Allergy 1999, 54, 229±234. Copyright # Munksgaard 1999 ISSN 0105-4538 Exposure to an abundance of cat (Fel d 1) and dog (Can f 1) allergens in Swedish farming households Several studies have shown that exposure to indoor allergens derived from furred pets is an important cause of respiratory allergy (1, 2). A recent study from Sweden, performed as part of the European Community Respiratory Health Survey, has demonstrated a higher prevalence of sensitization to domestic animals, especially to cats, than sensitization to other indoor allergens such as mites (3), probably due to both Key words: Can f 1; cat allergen; dog allergen; exposure; farmers; Fel d 1; sensitization. Background: Earlier studies have shown that farmers are to a low degree sensitized to animal allergens. We have measured the amount of cat (Fel d 1) and dog (Can f 1) in farm households and examined the relationship between exposure and sensitization to cat and dog allergens. Methods: Dust samples from the homes of 403 farmers who had participated in an epidemiologic follow-up study on respiratory symptoms were analyzed for allergen content by two-site ELISA methods. Results: Fel d 1 was detected in 99.5% of the farmers' households ranging from 0.055 to 1455 mg/g dust in mattresses (GM 13.2) and to 3775 mg/g dust in living-room carpets (GM 17.1). Can f 1 was detected in 90.6% of the households from 0.2 to 116 mg/g dust in mattresses (GM 2.0) and to 504 mg/g dust in carpets (GM 4.3). Homes with pets present had the highest levels of the allergens (P,0.001). A total of 8.4% and 7.4% of the farmers were sensitized to cat and dog, respectively. A signi®cant correlation was noted between exposure to the allergens and speci®c IgE to cat and dog, respectively (P,0.001). Sensitization to cat (OR~4.9) and dog (OR~17.8) was signi®cantly associated with asthma. Conclusions: In spite of the abundance of Fel d 1 and Can f 1, farmers are only to a low degree sensitized to cats and dogs. 229