Dampness in dwellings and its associations with asthma and allergies among children in Chongqing: A cross-sectional study

The city of Chongqing has high outdoor temperatures and humidity throughout the year and consequently a high risk of dampness and mold problems in dwellings. As part of the China, Children, Homes, Health (CCHH), associations between home characteristics and children’s asthma, allergies, and related symptoms were investigated in Chongqing, China. A cross-sectional questionnaire survey on home characteristics including dampness and symptoms of asthma and allergies in 5299 children was performed. Data for 4754 children (3–6 years) and their homes were analyzed. Results showed that 35.1% of homes were reported to have “damp bedding”, 14.3% “condensation on window panes (higher than 5 cm)”, 11.6% “mouldy odor”, 9.3% “water leakage”, 8.3% “damp stains” and 5.3% “visible mould”. Wheezing and rhinitis ever were reported for 27.0% and 51.1% children respectively, and rhinitis, wheezing, cough at night and eczema in the last 12 months were reported for 38.1%, 20.5%, 18.9% and 13.2% respectively. Doctor-diagnosed asthma was reported for 8.3% of children, and doctor-diagnosed rhinitis for 6.2%. Dampness in homes was generally strongly associated with asthma and allergies among Chongqing children. The strongest association was found between “visible mould” and doctor-diagnosed rhinitis, and the adjusted Odds Ratio (OR ^A ) was 2.27 (95% CI: 1.48, 3.49). “Damp bedding” was significantly associated with all asthma and allergic symptoms, but doctor-diagnosed asthma and rhinitis. The behavior of “putting bedding to sunshine” could effectively reduce the prevalence of asthma and allergic symptoms, and the risk of bedding affected with damp was reduced significantly when bedding was put to sunshine frequently.