Methods: We conducted a systematic review to determine whether antimicrobial surfaces used in patient rooms in the healthcare setting reduce the incidence of HAI or antibiotic resistant organisms (ARO) or reduce microbial contamination. Relevant databases were searched. Experimental and quasi-experimental designs were included if they evaluated surfaces or surface treatments with persistent antimicrobial activity. Eligibility review and data abstraction were performed in duplicate. The Cochrane EPOC tool was used to assess risk of bias (ROB) and the GRADE system was used to determine the strength of the evidence.
Results: From 6060 records, 11 studies were included (Figure 1). Interventions included copper (7), silver (1), or metal-alloy (1) surfaces and surface treatment with organosilane (2). All studies evaluated microbial contamination as an outcome. Copper surfaces reduced microbial contamination by a median (range) of <1 log (<1 log to 2 logs). The organosilane studies showed conflicting results (3 vs. 0 log reduction in contamination). Two studies evaluated HAI and/or ARO. An RCT of copper surfaces in an ICU demonstrated a 58% reduction in HAI (p<0.05) and a 64% reduction in ARO (p=ns) but was not properly randomized or blinded (GRADE evidence level: low). An uncontrolled before-after study in a long term care unit found a 24% reduction in HAI (p<0.05) but ROB was high due to the study design (GRADE evidence level: very low). The GRADE quality of evidence for an association between copper surfaces and HAI reduction was further downgraded due to the limited number of studies, risk of publication bias, and lack of non-industry sponsored studies.
Conclusion: Copper surfaces in clinical settings reduce microbial contamination by 0-1 log although the clinical significance of this is uncertain. Two studies demonstrate a reduction in HAI with copper surfaces, but both were at high ROB. The overall GRADE quality of evidence is very low. Future studies are required to confirm these findings.
M. P. Muller,
M. Lim, None