The efficacy of a simulated tunnel washer process on removal and destruction of Clostridioides difficile spores from health care textiles

Am J Infect Control. 2019 Nov;47(11):1375-1381. doi: 10.1016/j.ajic.2019.04.180. Epub 2019 Jun 22.

Abstract

Background: Research on reducing Clostridioides difficile spore contamination of textiles via laundering is needed. We evaluated the sporicidal properties of 5 laundry chemicals and then determined the ability of a peracetic acid (PAA) laundry cycle to inactivate and/or remove spores from cotton swatches during a simulated tunnel washer (TW) process.

Methods: In phase I, spore-inoculated swatches were immersed in alkaline detergent, sodium hypochlorite, hydrogen peroxide, or PAA for 8 minutes. In phase II, inoculated swatches were passed through a simulated 24-minute TW process employing 5 wash liquids. Spore survivors on swatches and in test chemical fluids in both studies were enumerated using standard microbiologic assay methods.

Results: In phase I, hypochlorite solutions achieved >5 log10 spore reductions on swatches and >3 log10 reductions for wash solutions. PAA achieved minimal spore reduction in the wash solution (0.26 log10). In phase II, the PAA equilibrium-containing process achieved a >5 log10 spore reduction on swatches. In wash solution tests, the cumulative spore reduction peaked at >3.08 log10 in the final module.

Conclusions: Sodium hypochlorite as a laundry additive is sporicidal. The cumulative effects of a TW process, coupled with a PAA bleach agent at neutral pH, may render textiles essentially free of C difficile spore contamination.

Keywords: Infection prevention; Laundry chemicals; Peracetic acid; Simulated laundry process; Sodium hypochlorite; Tunnel washer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Clostridiales*
  • Decontamination / methods
  • Detergents / pharmacology*
  • Disinfectants / pharmacology*
  • Hydrogen Peroxide / pharmacology
  • Laundering*
  • Sodium Hypochlorite / pharmacology
  • Spores, Bacterial / drug effects*
  • Textiles / microbiology*

Substances

  • Detergents
  • Disinfectants
  • Hydrogen Peroxide
  • Sodium Hypochlorite