Purpose

The healthcare field is struggling with urgent questions about how to respond to the current COVID-19 pandemic. Health systems, clinicians, policymakers, and the general public want evidence to inform critical decisions. In this period of clinical uncertainty, the AHRQ Evidence-based Practice Center (EPC) Program has rapidly summarized the current available evidence in response to urgent questions about promising options to control the COVID-19 pandemic.

This rapid review can help healthcare decision makers know what evidence is available, what evidence will soon be available, and what areas are most promising for future research. The review examined this question:

1. What data exist for the effectiveness of no touch modalities for disinfecting patient rooms in hospital or acute care settings for:
   1. Respiratory viral pathogens
   2. Other pathogens with potential relevance to assessing efficacy vs. SARS-CoV-2 (specifically Clostridioides [formerly Clostridium] difficile [CD] spores)

The no-touch modalities included in this report were: ultraviolet light (UVL), vaporous hydrogen peroxide (VHP), aerosolized hydrogen peroxide + silver ions, solid copper surfaces, steam, chlorine dioxide, and ozone

Evidence Summary

UVL

• Respiratory viruses:
  • One pre/post study found cleaning with quaternary ammonium agents + UVL was associated with a 44 percent unadjusted reduction on overall incidence of respiratory viral infection; however, the study was small, with potential confounding.
• Clostridioides difficile infection (CDI):
  • Meta-analysis of 11 studies of various designs found UVL was associated with lower CDI rates: relative risk (RR): 0.64 (95% confidence interval [CI]: 0.49 to 0.84).
  • Pre/post studies had consistent positive results; however, controlled trials had conflicting results. One additional interrupted time series found no difference in infection rates for UVL + bleach compared with bleach.
  • Two small pre/post studies found UVL + standard cleaning lowered surface contamination, but a third small pre/post study found no difference between UVL + bleach vs. bleach. Another small pre/post study found that compared to standard cleaning (with bleach), UVL + standard cleaning was associated with non-statistically significant lower surface contamination on high touch surfaces.

VHP/Aerosolized Hydrogen Peroxide

• Respiratory viruses: No studies identified.
• CDI:
  • Pooled analysis of five noncontrolled studies found nonstatistically significant lower CDI rates: RR: 0.52 (95% CI: 0.15 to 1.81). One additional pre/post study also found VHP lowered CDI.
  • One small randomized controlled trial (RCT) study compared aerosolized hydrogen peroxide + silver ions to bleach and found no statistically significant difference in surface contamination.

Solid Copper Surfaces

• Respiratory viruses: No studies identified.
• CDI:
  • One pre-post study of copper surfaces found copper surfaces reduced CDI infection rates: 2.4 vs. 0.7 per 1,000 patient-days; however, authors noted serious potential confounding in the results. A second pre/post study also found lower CDI rates associated with copper surfaces + copper linens: incidence rate 4.1 (95% CI: 4.05 to 4.14) to 0.69 (95% CI 0.65 to 0.73). However, serious potential confounders including differences in patient mix and room size were noted.

Steam, Ozone, Chlorine Dioxide

• No studies identified for respiratory viruses or CDI.

Conclusions

The effectiveness of no-touch disinfection modalities for disinfecting hospital rooms to decrease respiratory viral infections and CDI remains unclear. Although more than a dozen studies of UVL disinfection systems exist, weak study design and conflicting results prevent definite conclusions. The evidence base for VHP and solid copper surfaces is also weak. For VHP, although five noncontrolled studies found an association with lower CDI, studies had important flaws. Only a single small RCT assessed aerosolized hydrogen peroxide vapor + silver, and only two pre/post studies assessed solid copper surfaces.

Higher quality studies, particularly RCTs, are needed to assess the impact of these no-touch modalities for disinfecting hospital rooms. Also, studies directly assessing efficacy for respiratory viruses are vital. Future studies should include detailed descriptions of what procedures "standard" terminal cleaning involves along with the degree of adherence or efforts to monitor fidelity. Studies should also describe other quality-improvement interventions initiated around or during the study period and other potential confounders (e.g., antimicrobial stewardship, compliance with hand hygiene and isolation precautions) that could potentially affect infection rates.

Citation

Tsou AY, Pavlides S, Koepfler L, Drummond C. No-Touch Modalities for Disinfecting Patient Rooms in Acute Care Settings. Rapid Evidence Product. (Prepared by the ECRI Evidence-based Practice Center under Contract No. 290-2015-00005-I). AHRQ Publication No. 20(21)-EHC021. Rockville, MD: Agency for Healthcare Research and Quality. October 2020. Posted final reports are located on the Effective Health Care Program search page. DOI: 10.23970/AHRQEPCCOVIDNOTOUCH.