In healthcare environments, the effective removal of microbial contamination from frequently touched surfaces is of paramount importance to ensure patient safety and prevent the spread of infections. Achieving this goal depends on a combination of mechanical cleaning, suitable disinfectants, and adherence to established protocols [1,2]. However, conditions in a clinical setting are often more complex than in a controlled laboratory environment, leading to potential discrepancies between test results and real-world efficacy [3,4].
Ultraviolet C (UV-C) radiation has gained attention as a potential tool for surface disinfection due to its demonstrated efficacy against a wide range of microorganisms in controlled laboratory studies [5,6]. These studies, however, have revealed variations in UV-C dosages required for specific reductions in microbial load [7]. Furthermore, the conditions of laboratory tests may not adequately mimic the diverse and dynamic settings of healthcare facilities, where various surface materials, organic soils, and different types of pathogens are encountered [8].
The current study by Knobling et al.addresses this gap by developing a field test to evaluate the effectiveness of automated UV-C disinfection compared to manual disinfection using alcohol-based ready-to-use disinfection wipes (Bacillol® AF Tissues). The aim was to evaluate the performance of these two methods under real clinical conditions [9].
In the study, samples were collected from naturally contaminated surfaces in a medical examination room both before and after disinfection. Log reduction values (LRVs), a measure to describe the reduction of microorganisms, and disinfection success were then evaluated for both UV-C radiation and manual disinfection using pre-soaked alcohol wipes. The study identified surfaces that were regularly and uniformly contaminated with bacteria, making them particularly suitable for field testing. Mean contamination levels were significantly reduced, from 23.3 to 1.98 colony forming units per square centimeter (cfu/cm²) with UV-C disinfection, and from 29.7 to 0.26 cfu/cm² with manual disinfection. In terms of disinfection success, manual disinfection showed a higher rate of 98.1% compared to 75.5% for UV-C [9].
The findings of this study indicate that fully compliant manual disinfection results in higher log reduction values and disinfection success rates compared to automated UV-C disinfection. However, UV-C disinfection, when used alongside manual cleaning, has the potential to improve overall disinfection performance in healthcare settings. This suggests that a combined approach, leveraging both UV-C radiation and manual disinfection, may offer a comprehensive solution for achieving optimal surface decontamination in clinical environments – particularly in high-risk areas or when dealing with patients carrying highly tenacious pathogens [9].
Sources:
1. Hall L, Mitchell BG. Cleaning and decontamination of the healthcare environment. In: Decontamination in hospitals andhealthcare. Elsevier; 2020. p. 227e39.
2. Otter JA, Yezli S, Barbut F, Perl TM. An overview of automated room disinfection systems: when to use them and how to choose them. In: Decontamination in hospitals and healthcare. Elsevier; 2020. p. 323e69.
3. Wu Y-L, Yang X-Y, Ding X-X, Li R-J, Pan M-S, Zhao X, et al. Exposure to infected/colonized roommates and prior room occupants increases the risks of healthcare-associated infections with the same organism. J Hosp Infect 2019;101:231e9.
4. Cohen B, Cohen CC, Løyland B, Larson EL. Transmission of health care-associated infections from roommates and prior room occupants: a systematic review. Clin Epidemiol 2017;9:297e310.
5. Masjoudi M, Mohseni M, Bolton JR. Sensitivity of bacteria, protozoa, viruses, and other microorganisms to ultraviolet radiation. J Res Nat Inst Stand Tech 2021;126:126021.
6. Mariita RM, Randive RV. Disinfection of methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium and Acinetobacter baumannii using Klaran WD array system. Access Microbiol 2021;3:194.
7. Demeersseman N, Saegeman V, Cossey V, Devriese H, Schuermans A. Shedding a light on ultraviolet-C technologies inthe hospital environment. J Hosp Infect 2023;132:85e92.
8. Knobling B, Franke G, Belmar Campos C, Büttner H, Christner M, Klupp EM, et al. Tolerance of clinical vancomycin-resistant Enterococcus faecium isolates against UV-C light from a mobile source. Antimicrob Resist Infect Control 2023;12(1):63.
9. Knobling B, Ulatowski A, Franke G, et al. Superiority of manual disinfection using pre-soaked wipes over automatic UV-C radiation without prior cleaning. J Hosp Infect., 2023;140:72-78.
