Allergic sensitization owing to 'second-hand' cat exposure in schools.

Abstract

Environmental allergen loads play an important role in triggering symptoms in atopic individuals. While a number of previous studies have shown that cat allergens (Fel d 1) can be found in school dust samples, no study has provided evidence that public places contribute to increased atopic sensitization rates in children. We employed data collected in a health survey of school children living in Germany in order to examine the association between the proportion of class- and schoolmates reporting cat contact and sensitization rates in children. Among 1893 children, 8.7% were sensitized to cats. Those sensitized were 5-7 times more likely to have received an asthma diagnosis or to have reported wheezing. Pupils without regular contact with cats were twice as likely to test positive for major cat allergen when the proportion of schoolmates with cat contact was high. No such relation was observed amongst children reporting regular cat contact. Our study suggests that allergens in school environments contribute to allergic sensitization and atopic diseases such as asthma. Thus, methods to reduce the allergen load in classrooms should be considered.