Efficacy of UV-C devices in Clostridioides difficile environmental decontamination in a hospital setting: a before-after study

Clostridioides difficile infection (CDI) is a leading healthcare-associated infection, with significant morbidity, mortality, and healthcare costs. Effective environmental decontamination is critical for infection control, as C. difficile spores persist on surfaces despite standard cleaning protocols. Ultraviolet (UV) light devices have been proposed as adjuncts to standard disinfection methods, yet their real-world effectiveness in reducing environmental contamination remains unclear. This study evaluates the impact of UV devices on environmental contamination in hospital rooms previously occupied by symptomatic CDI patients and asymptomatic C. difficile carriers. We conducted a prospective interventional before-after study in a tertiary hospital’s internal medicine wards. Environmental samples were collected from ten high-touch sites in 33 rooms occupied by CDI patients (n = 5) or asymptomatic carriers (n = 28). Following routine daily cleaning with sodium hypochlorite (bleach), UV disinfection was performed, and samples were taken before and after UV application using sponge environmental wipes and cultured to quantify colony-forming units (CFUs). A contamination scale (0–4) was used to assess overall contamination levels, incorporating both CFU counts and the number of affected sites. Statistical analysis included Student’s t-test and chi-square tests. Before UV disinfection, 27% (9/33) of rooms were classified as heavily contaminated, and 12% (4/33) had medium contamination. After UV application, 21% (7/33) remained heavily contaminated, while 18% (6/33) exhibited medium contamination (p = 0.46). The mean contamination scale score decreased from 1.94 ± 1.56 to 1.58 ± 1.64 (p = 0.08). No significant reductions were observed in CFU couants (29.61±61.07 before vs. 17.97 ± 42.53 after, p = 0.1) or the number of contaminated sites (2.24±2.26 before vs. 1.91 ± 2.19 after, p = 0.07). Our findings suggest that adding UV disinfection after daily bleach cleaning did not significantly reduce C. difficile contamination. Further evidence is needed to determine the potential added value of UV technology.