Hospital acquired infections are the sixth leading cause of death in the US. The hospital environment serves as a significant source of microbes making patients vulnerable to infections. High-intensity narrow-spectrum light (HINSL) has been shown to inactivate a wide range of bacterial pathogens by the photoexcitation mechanism. Our pilot study aims to investigate the impact of the application of a 405-nanometer HINSL in the reduction of Staphylococcus species in 2 Medical Intensive Care Unit (MICU) suites at our institution.
Twenty contact sites were sampled from each of the 2 MICU suites. One or two samples of 60 cm2 were obtained from each site using a moistened swab. Samples were taken at 7:00 AM, 3 days per week for 4 weeks. 105 samples per week were obtained from each suite. Each sample was then plated on Baird Parker Media which identifies Staphylococcus species. After 48 hours of incubation, the number of colony-forming units (CFU)/plate were quantified with each CFU representing one colony of Staphylococcus species (CSS). Samples were collected in the absence of HINSL during weeks 1 and 4. HINSL was turned on from 7:00 AM - 9:30 PM via 2 ceiling installed units located on either side of the patient bed during weeks 2 and 3. Other ceiling lights were not on during HINSL use. Routine cleaning of MICU suites remained in place throughout the study. The cumulative total of CSS between weeks for both MICU suites was analyzed.
840 plates were analyzed over the 4-week period yielding a cumulative total of 3479 CSS. 2456 CSS were identified in week 1. This decreased to 275 CSS in week 2 and equaled to an 88.8% reduction. Week 3 had a total of 14 CSS, resulting in a 94.9% reduction when compared to week 2, and a 99.4% reduction in comparison to week 1. There was an increase from 14 CSS in week 3 to 1234 CSS in week 4, amounting to an 8714% increase in CSS.
Terminal cleaning of hospital suites is an accepted method to prevent hospital-acquired infections. Our study revalidates that the use of HINSL as a complimentary cleaning protocol may aid in the environmental decontamination of Staphylococcus species. Robust studies are needed to demonstrate clinical impact on hospital-acquired infection rates with the implementation of this novel technology.
D. Wyatt, None
N. Bhanot, None
Z. Min, None
J. Thomas, None