Can coating ward environment with visible light activated photocatalyst reduce hospital acquired infection rate?

Abstract

Introduction It is well proven that hospital environment actually hosts a significant amount of micro-organism, including drug resistant pathogens. However, managing environmental microbial burden has received inadequate attention. There was a handful of small-scaled studies investigating the usage of antibacterial material in ward, such as copper and silver. Outcome assessment was quantitative culture from the coated surface. It is also impractical to utilise these alloys to coat the entire clinical area. These materials are also not compatible with post-hoc application, hence, most hospitals would not benefit from using these alloys. Furthermore, a huge gap exists between clinical outcome and the utilisation of these materials. A commercially available spray coat, named Visible Light Activated Photocatalyst (VLAP) can decompose organic substance (including bacteria and viruses) by oxidative process when under illumination. Application is simple and is feasible in most locations. And upon fixation, the coating is resistant to wear. It has no consumption issue because it acts by catalysis, theoretically without depletion. And its oxidative process offers a broad spectrum bacteriocidal and virocidal effect. This commercially available product has stood a good safety profile after launching for more than a decade. Despite it sounds ideal as a means of infection control, its efficacy was only proven in domestic and industrial setting, and there was no report on its use in clinical setting. Objectives To study if the use of VLAP as antibacterial coating for ward environment can lower microbial burden as well as infection rate. Methodology It is a prospective randomised single blinded controlled trial. Half of the male and female orthopaedic rehabilitation ward was spray coated with VLAP. Bed allocation of inpatients were randomised to these cubicles and they were cohorted for infection, fever and prescribed with antibiotics during their hospitalisation. Monthly monitoring of the environmental bioburden was assayed by adenosine triphosphate luminometer. Results VLAP reduced the environmental microbial burden by 94.2% (4.8 relative light units vs 74.2 relative light units). 1,371 patients satisfied the cohort criteria and contributed 22,328 bed days. The control group had urinary tract infection, chest infection, fever and antibiotic prescription episode as 0.797, 0.186, 0.379 and 1.05 per 100-bed-day respectively. Surgical site infection rate for clean surgery in the control group was 3.64%. VLAP reduced these parameters by 56.9%, 61.9%, 20.3%, 51.6% and 53.0% respectively. No new onset of allergy or dermatitis were reported. Conclusions VLAP effectively lowered environmental microbial burden. Clinical infection rate and utilisation of antibiotics were also effectively reduced.