Effect of ozone gas on cultures of Candida albicans and Aspergillus fumigatus: evaluation of two ozonation devices.

INTRODUCTION: Candida albicans and Aspergillus fumigatus are two important agents of Healthcare-associated infections. This study aimed to evaluate the antifungal activity of ozone (O3) gas produced by two commercial devices against cultures of these two species. METHODOLOGY: Sterile plastic plates were inoculated with C. albicans and A. fumigatus and placed on a countertop at three distances (30 cm, 1 m, and 2 m) and three positions in relation to the wall (near, middle, and away), considering the source of O3. Plates were exposed to O3 for one hour and incubated. After incubation, the counting of colony-forming units was performed. As a control, an inoculated plate was incubated, without being exposed to O3. Tests were carried out with two different devices (namely, Mod.I and Mod.II), with the air conditioner on and off, in triplicate. RESULTS: Both devices showed antifungal activity. Mod. I presented better results, due to a higher flow rate. The best activity was on plates at 30 cm, middle position. Contrarily, on plates at 2m, near the wall, the inhibition activity was lower. The best results were obtained with the air conditioner off. Candida albicans was more sensitive to O3 than A. fumigatus. CONCLUSIONS: This method of decontamination by O3 gas shows potential due to its fast and easy execution. The establishment of new protocols for hygiene and hospital disinfection using this approach should be considered, which may reduce environmental contamination by fungi and, consequently, the burden of fungal infections.

Assessment of Soiling on Highly Touched Clinical Surfaces in Intensive Care Units.

AIM: The aim of this study is to evaluate highly touched clinical surfaces using visual inspection methods and adenosine triphosphate by bioluminescence to identify soiling in intensive care units. METHOD: Descriptive, cross-sectional study carried out in three intensive care units located in Belo Horizonte, MG, Brazil. Data collection included 142 assessments of environmental surfaces. For data analysis, the Pareto diagram and descriptive statistics were used through measures of central tendency. RESULTS: The visual inspection identified dirtiness in the infusion pump, alcohol dispenser, and telephone. The surface that showed a high level of contamination by organic matter identified by the adenosine triphosphate bioluminescence test was the telephone, with a median of 1012 RLU/cm2 (±348.8). CONCLUSION: The surface evaluation methods used in the intensive care units made it possible to identify dirt on surfaces highly touched by hands, reinforcing the need for investments in training and audits in the process of cleaning and disinfecting surfaces.