Skin-prick test findings in students from moisture- and mould-damaged schools: A 3-year follow-up study

Dampness and moisture problems in a building may cause growth of moulds, le ading to sensitization and symptoms in the inhabitants. The mechanism by wh ich sensitization to moulds takes place has remained obscure; in particular , the role of atopy is not clear. In 1996, 622 pupils (7-13 years of age) a ttending a school with a moisture problem (index school; 414 pupils) and a control school (208 pupils) were screened using a questionnaire. Two-hundre d and twelve children had doctor-diagnosed asthma, parental-reported wheezi ng or prolonged cough, and they participated in a clinical study, which inc luded skin prick tests (SPT) to 12 moulds. An identical, follow-up study wa s performed 3 years later in 1999. In the follow-up study, 144 of the origi nal 212 students participated. They were now attending four different schoo ls: the index primary school had been renovated and the control school rema ined unchanged, but the two secondary schools had moisture and mould proble ms. The purpose of the study was to evaluate the occurence of mould allergy in children of school age and to compare sensitization to moulds in relati on to age, exposure, asthma, and atopy. In 1999, SPT responses to moulds we re demonstrated in 17 (12%) of the 144 children. Six children had SPT react ions greater than or equal to3 mm and all but one were older than 14 years. During the 3-year follow-up period, mould allergy developed in five childr en and disappeared in two children. Five of the six children with reactions greater than or equal to3 mm to moulds had positive responses to other all ergens, five had clinical atopy but only two had asthma. Likewise, all six children had been exposed to moisture and dampness in the school buildings. In conclusion, mould allergy diagnosed by SPTs was rare in students. Most reactions to moulds were in students older than 14 years with multiple SPT reactions to common allergens, and there was no significant association wit h asthma.