Infections in child day care centers and later development of asthma, allergic rhinitis, and atopic dermatitis: prospective follow-up survey 12 years after controlled randomized hygiene intervention

Objective To evaluate the effect of prevention of common infections in child day care centres (CDCCs) on the later development of allergic disease. Children _2 years of age were recruited from 20 CDCCs in Finland for a 15-month randomised, controlled hygiene intervention trial conducted in 1991–1992. Among the children in the intervention CDCCs, there were 27% fewer episodes of acute otitis media and 24% fewer days of antimicrobial agents. Methods Questionnaires were sent in 2003 (12 years later) to 1376 participants of the previous intervention trial; 928 participated (response rate: 68%). The main outcome measures were the number of respondents with a physician diagnosis of asthma, allergic rhinitis, and/or atopic dermatitis (AD) and those who reported symptoms of atopic disease. Results No differences were found between the intervention and control groups with regard to rates of asthma, allergic rhinitis, or AD or with frequency of atopic symptoms. Conclusions The prevention of common respiratory tract and enteric infections during early childhood does not change later allergic morbidity.