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

Abstract

Dampness and moisture problems in a building may cause growth of moulds, leading to sensitization and symptoms in the inhabitants. The mechanism by which 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) attending a school with a moisture problem (index school; 414 pupils) and a control school (208 pupils) were screened using a questionnaire. Two-hundred and twelve children had doctor-diagnosed asthma, parental-reported wheezing or prolonged cough, and they participated in a clinical study, which included skin prick tests (SPT) to 12 moulds. An identical, follow-up study was performed 3 years later in 1999. In the follow-up study, 144 of the original 212 students participated. They were now attending four different schools: the index primary school had been renovated and the control school remained unchanged, but the two secondary schools had moisture and mould problems. The purpose of the study was to evaluate the occurrence of mould allergy in children of school age and to compare sensitization to moulds in relation to age, exposure, asthma, and atopy. In 1999, SPT responses to moulds were demonstrated in 17 (12%) of the 144 children. Six children had SPT reactions > or = 3 mm and all but one were older than 14 years. During the 3-year follow-up period, mould allergy developed in five children and disappeared in two children. Five of the six children with reactions > or = 3 mm to moulds had positive responses to other allergens, 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 with asthma.

Effects of Airflow and Changing Humidity on the Aerosolization of Respirable Fungal Fragments and Conidia of Botrytis cinerea

“…The lack of germinability of microconidia and the importance of exposure to airflow or mechanical handling to cause particle aerosolization may be reasons why, as concluded in a review paper, B. cinerea is not measured to be among the dominating fungi in indoor air (26). The facts that B. cinerea is able to grow on building materials and on many common fruits and vegetables, that it produces microconidia and particles smaller than conidial size, and that relatively many people are allergic to B. cinerea (24,27,30,31) may indicate that exposure to B. cinerea is more common than what has been measured in exposure studies. The allergenic properties of B. cinerea spores are higher if they are germinated (17), but how often they are present in the air as germinated micro-or macroconidia is not known.…”

Moisture damage and childhood asthma: a population-based incident case–control study

“…Moulds can induce the production of specific IgE antibodies, which are related to severity of asthma [25]. However, the association between moisture damage or mould growth and IgE production is very weak [26]. Therefore, non-IgE-mediated mechanisms are more likely.…”

“…For instance, the observed levels of volatile organic compounds in damaged homes are usually considerably lower than the levels that would cause irritation [33]. Given the lack of evidence for IgEmediated sensitisation [1,26] and the low indoor levels of most measured irritants in moisture-damaged buildings [34], it is tempting to speculate that the underlying mechanism involves some, as yet unknown, immunological reactions. Unfortunately, due to the low number of specific IgE results among the controls, the present authors were not able to study the association between moisture damage and development of atopy or the potential effect modification by atopy.…”

Moisture Damage and Asthma: A Birth Cohort Study

“…Only a small proportion of exposed people are sensitized to molds. 25 Exposure to moisture damage or mold may cause allergy-like symptoms due to histamine release 4 without measured IgE levels. Repeated irritation in the respiratory tract might lead to long-lasting inflammation and inflammationrelated diseases (eg, asthma).…”