Assessment of an Ultraviolet AirSterilizer on the Incidence ofChildhood Upper Respiratory TractInfections and Day Care CentreIndoor Air Quality

A double-blind trial was conducted to evaluate the effect of an ultraviolet air sterilizer in reducing the incidence of upper respiratory infections in children and the concentration of micro-organisms in 3 day-care centres located in Montreal. A population of 122 children (12-36 months of age) was under daily surveillance for respiratory illness during an average period of 12 weeks. Four ultraviolet and four control units were placed in the children’s rooms. Indoor parameters were measured in four rooms, before and after installation of the devices. Even when a reduction in concentration of indoor micro-organisms was observed, the effect of the devices on the respiratory illness was negligible. The results suggest that the other routes of infection transmission are predominant in the day-care centre.