Indoor air quality and symptoms of acute respiratory infections and gastrointestinal issues in children and employees in day-care nurseries

Background: Children attending day-care centers (DCCs) experience more infections than those cared for at home and DCC employees have high sickness absence rates. This study aimed to investigate the association between indoor air quality and absenteeism among children and staff in DCCs. Methods: CO2 levels, relative humidity (RH), and temperature were continuously measured in 22 DCCs over 3 winter months. Simultaneously, absenteeism due to sickness was recorded for 721 children and 213 employees. In 11 DCCs, staff received training to improve ventilation. Results: The median CO2 concentration, RH, and temperature were 818 ppm, 38.7%, and 20.8 °C, respectively. Acute respiratory infections (ARIs) accounted for 42% of child absenteeism and 53% of staff absenteeism, while gastrointestinal symptoms (GI) were responsible for 24.7% and 27.3% of absenteeism in children and staff, respectively. No significant association was found between ARI absenteeism and CO2 concentration, RH, or temperature. However, a significant association was observed between GI and room temperature (P <.05). No significant differences in CO2 concentration or absenteeism were observed between intervention and control groups. Conclusions: No statistical evidence was found that ARI absenteeism was associated with the measured indoor air quality parameters. GI for staff and children was significantly associated with room temperature. Absenteeism was not associated significantly with targeted interventions.