Impact of a water-damaged indoor environment on kindergarten student absences due to upper respiratory infection

Children are relatively sensitive to health pollutants, including those in indoor environments. This study was conducted to explore the impact of a water-damaged indoor environment on childrenʹs weekly absences resulting from upper respiratory infection in a kindergarten. Twenty-six and 27 children were recruited from water-damaged and non-water-damaged classrooms in the same building, and 936 and 1017 person-weeks were followed up during the study period of 42 weeks. Weekly absence rates were computed from daily absence records. The weekly absence rate was significantly higher for children in the water-damaged classroom (2.99%) than for those in the non-water-damaged classroom (1.28%). After adjusting for gender and grade, the odds ratio for absence was 2.45 (95% CI: 1.15–5.24) for the children in the water-damaged classroom. Additionally, fungal concentration was significantly higher in the water-damaged classroom (993 CFU/m3) than in the non-water damaged classroom (404 CFU/m3). It is tentatively concluded that, in the subtropics, fungal concentration is a better indicator than humidity for early-stage water damage. Periodic fungal measurement is recommended to alter the water-damaged effect.