Two-step or one-step - are all methods for neonatal incubator decontamination equal?

Abstract

Healthcare-associated pathogens, including Staphylococcus capitis, can contaminate incubator surfaces and are of significant concern in neonatal intensive care units (NICUs). Effective incubator decontamination is essential for infection prevention and control, with submersion decontamination often recommended. This may not always be achievable, with wipe decontamination seen as an alternative. Here we compare the ability of a two-step (submersion in enzymatic detergent followed by wiping with hypochlorite-based wipes) with a one-step (wiping with quaternary ammonium compound-impregnated wipes) decontamination procedure to remove microbial surrogate markers from neonatal incubator surfaces. Three cauliflower-mosaic-virus-derived microbial surrogate markers were inoculated on to the fan, a mattress seam and the external arm port door clips of two Giraffe™ Omnibed™ Carestation™ incubators. Incubators were decontaminated either by the one-step or the two-step decontamination process. Swab samples were collected from 28 sites on each incubator and surrounding environment, with marker presence determined by qPCR. Following two-step decontamination, three of 28 (11%) sample sites were positive for any marker, compared with 12 of 28 (43%) after one-step decontamination. Markers were transferred to several incubator surfaces and recovered from the originally inoculated sites following one-step decontamination, with the marker inoculated on door clips having the greatest transfer. Markers inoculated on to the mattress persisted through both decontamination strategies. In conclusion, microbial surrogate markers were not completely removed from incubator surfaces by one-step decontamination alone. Two-step decontamination was the most effective method and removed markers from submergible surfaces, but not from the mattress. These findings indicate that micro-organisms can persist after incubator terminal decontamination, particularly on mattresses and when a two-step decontamination process is not used. This highlights the importance of effective decontamination practices to mitigate micro-organism persistence on incubator surfaces.

Keywords: Built environment; Decontamination; Environmental contamination; Infection prevention and control; Neonatal infections; Staphylococcus capitis.