Moisture damage is a very common problem in private houses, workplaces and public buildings around the world and has been associated with adverse respiratory symptoms, asthma and respiratory infections of inhabitants.

The authors of this new review, Dr Riitta Sauni et al, aimed to determine the effectiveness of remediating buildings damaged by dampness and mould in reducing or preventing the occurrence of respiratory tract symptoms, infections and symptoms of asthma.

The authors included eight studies with 6538 participants; three randomised controlled trials (RCTs) and five non-RCTs. The interventions aimed to remove mould and dampness from family houses, schools or, in one study, an office building. When remediation of houses was compared to no intervention at all, the authors found evidence that mould remediation reduced asthma-related symptoms and respiratory infections. It also decreased the use of asthma medication in asthmatics. The authors found very low-quality evidence that after repairing a mould-damaged office that asthma-related and other respiratory symptoms decreased.

For extensive remediation compared with information only, there was moderate-quality evidence that the number of asthma symptom days among asthmatic children did not decrease significantly. However, the number of emergency and inpatient visits decreased after the repair of the building. Pupil visits to physicians due to a common cold were less frequent after the building was repaired but respiratory symptoms (stuffy nose, runny nose, dry throat, hoarseness, eye irritation) were similar before and after the intervention both among pupils and adults working in the schools. Due to a wide range of outcome measures and variation in study designs, it was difficult to draw hard conclusions. Better research is needed, preferably with a cluster-RCT (cRCT) design and with more validated outcome measures.

Check out the full text here or listen to a podcast of the review in English or in Finnish.