Surface disinfection: evaluation of the efficacy of a nebulization system spraying hydrogen peroxide


Introduction. The study assessed the efficacy of a system of nebulization of a hydrogen peroxide-based solution for surface disinfection. Methods. Different concentrations (1, 2 and 4 ml/m3) of the same disinfectant solution (active principle: hydrogen peroxide) were nebulized inside a 50 m3 experimental environment. Sampling was carried out on both horizontal and vertical surfaces, and the total bacterial load at 37 °C was determined by means of direct contact with Rodac plates. The disinfection efficacy of the system was evaluated by comparing the total bacterial load measured on the surfaces before and after treatment. Statistical analysis was performed by means of Stata/SE9® software. Results. The percentage reduction in the mean bacterial load on horizontal surfaces as a result of treatment at concentrations of 1, 2 and 4 ml/m3 proved to be 54.9%, 70.9% and 86.9%, respec- tively. With regard to vertical surfaces, the percentage reduction was 100% in all experimental conditions. Discussion and conclusions. The system tested proved to be efficacious in disinfecting surfaces inside environments of 50 m3 in volume. It could therefore be used to disinfect surfaces in hos- pital and community settings. In healthcare facilities, disinfection by means of nebulization systems could help to reduce the risk of spreading nosocomial infections.