The effect of a proprietary chlorine-stabilizing surface-coating formulation on healthcare environment disinfection in multidrug-resistant bacteria isolation rooms

Abstract Objective OxiLast™ is a surface coating formulation that extends the antimicrobial effect of chlorine-based disinfectants. We sought to test it in a healthcare environment. Design Controlled quasi-experimental study with parallel groups and repeated measures, conducted in isolation rooms of chronically ventilated patients, carriers of carbapenem-resistant Acinetobacter baumannii (CRAB). Methods Standard sodium dichloroisocyanurate (NaDCC) disinfection was supplemented with OxiLast™ daily for 28 days at five patient stations, followed by twice-weekly application for 21 days. In parallel, six control stations were cleaned daily by NaDCC alone throughout the study. Environmental sampling targeted high touch surfaces adjacent to patient beds. Quantitative colony counts (CFU/cm2) and qualitative detection of CRAB and methicillin-resistant Staphylococcus aureus (MRSA) were performed at four time points: Day 0 (baseline), 21, 42, and 49. A decrease in environmental bioburden (target <5 CFU/cm 2 ), CRAB and MRSA detection were defined as the primary outcomes. Achieving these benchmarks following twice-weekly application for three weeks was defined as the secondary outcome. Results Baseline contamination averaged 1,272 CFU/cm 2 (median 800 CFU/cm 2 ) and 17,172 CFU/cm 2 (median 756 CFU/cm 2 ) in the control and intervention rooms, respectively. CRAB was detected in all stations of both groups, MRSA was detected in 4/6 and 5/5 of the control and intervention stations, respectively. On Day 21 following daily NaDCC-OxiLast™, all intervention stations dropped below 5 CFU/cm 2 (mean 2.07 CFU/cm 2 ). The control group averaged 316 CFU/cm 2 . CRAB and MRSA were detected in 5/6 of the control and in 1/5 and 0/5 in the intervention stations, respectively. Following twice-weekly NaDCC-OxiLast™ cleaning for 21 days, on Day 49, 4/5 intervention stations reached <5 CFU/cm 2 (averaging 1.33 CFU/cm 2 ), CRAB was undetected and MRSA was detected in 1/5 stations. All control stations remained >5 CFU/cm 2 , averaging 253 CFU/cm 2 , CRAB and MRSA were detected in 5/6 and 6/6 stations, respectively. At Days 21 and 49, the odds ratio for both CRAB and MRSA contamination in intervention rooms, was 0.026 (95% CI 0.00–0.43; p = 0.008). Conclusions These findings provide proof-of-concept for an extended-action protocol using OxiLast™ adjunct to NaDCC. The impact of this intervention on MDRO transmission and clinical infections should be further studied.