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

Abstract

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. 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. 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. 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.