Rito Beatriz, Matos Leonor, Proença Diogo N, Morais Paula V
University of Coimbra, Centre for Mechanical Engineering, Materials and Processes, ARISE, Department of Life Sciences, Calcada Martim de Freitas, 3000-456, Coimbra, Portugal.
Heliyon. 2024 May 4;10(10):e30738. doi: 10.1016/j.heliyon.2024.e30738. eCollection 2024 May 30.
Controlling the microbial load in the environment is crucial to prevent the spread of organisms. The continuous spread of nosocomial infections in hospital facilities and the emergence of the coronavirus (COVID-19) highlighted the importance of disinfection processes in health safety. This work aimed to evaluate the effectiveness of LED-based disinfection lamps on bacteria from the ESKAPEE group and virus phage in vitro inactivation to be applied in hospital environments and health facilities disinfection. This study evaluated the effect of different UV wavelengths (275 nm, 280 nm (UVC), 310 nm (UVB) and 340 nm (UVA)) on the disinfection process of various microbial indicators including , , , and Bacteriophage lambda DSM 4499. Exposure time (5 min-30 min), exposure distance (0.25 m and 0.5 m) and surface materials (glass, steel, and polished wood) were evaluated on the disinfection efficiency. Furthermore, the study determined the recovery capacity of each species after UV damage. UVC-LED lamps could inactivate 99.99 % of microbial indicators after 20 min exposures at a 0.5 m distance. The exposure time needed to completely inactivate , , , and Bacteriophage lambda DSM 4499 can be decreased by reducing the exposure distance. UVB-LED and UVA-LED lamps were not able to promote a log reduction of 4 and were not effective on or bacteriophage lambda DSM 4499 inactivation. Thus, only UVC-LED lamps were tested on the decontamination of different surface materials, which was successful. showed the ability to recover from UV damage, but its inactivation rate remains 99.99 %, and spores from were not completely inactivated. Nevertheless, the inactivation rate of these indicators remained at 99.99 % with 24 h incubation after UVC irradiation. UVC-LED lamps emitting 280 nm were the most indicated to disinfect surfaces from microorganisms usually found in hospital environments.
控制环境中的微生物负荷对于防止生物体传播至关重要。医院设施中医院感染的持续传播以及冠状病毒（COVID-19）的出现凸显了消毒过程在健康安全方面的重要性。这项工作旨在评估基于LED的消毒灯对ESKAPEE组细菌和病毒噬菌体的体外灭活效果，以应用于医院环境和卫生设施消毒。本研究评估了不同紫外线波长（275nm、280nm（UVC）、310nm（UVB）和340nm（UVA））对包括、、、和噬菌体λ DSM 4499在内的各种微生物指标消毒过程的影响。评估了暴露时间（5分钟 - 30分钟）、暴露距离（0.25米和0.5米）和表面材料（玻璃、钢铁和抛光木材）对消毒效率的影响。此外，该研究还确定了紫外线损伤后各物种的恢复能力。UVC-LED灯在0.5米距离照射20分钟后可使99.99%的微生物指标失活。通过缩短暴露距离，可以减少完全灭活、、、和噬菌体λ DSM 4499所需的暴露时间。UVB-LED灯和UVA-LED灯无法实现4个对数级的减少，对或噬菌体λ DSM 4499的灭活无效。因此，仅对UVC-LED灯进行了不同表面材料的去污测试，测试成功。显示出从紫外线损伤中恢复的能力，但其失活率仍为99.99%，并且的孢子未被完全灭活。然而，在UVC照射后24小时孵育后，这些指标的失活率仍保持在99.99%。发射280nm的UVC-LED灯最适合对医院环境中常见的微生物进行表面消毒。
