Surface area wiped, product type, and target strain impact bactericidal efficacy of ready-to-use disinfectant Towelettes

Abstract

BackgroundDisinfectant products are often used on environmental surfaces (e.g. countertops, patient beds) and patient care equipment in healthcare facilities to help prevent the transmission of healthcare-associated infections. Ready-to-use (RTU) disinfectants in the form of pre-wetted towelettes are increasingly popular among healthcare facilities. Currently, the EPA does not require disinfectant manufacturers to include a recommended maximum surface area per towelette on their product labels. The objective of this study was to investigate the efficacy of disinfectant towelette products on a hard non-porous surface across different coverage areas using a quantitative EPA method. We hypothesized that there would be significant differences in the efficacy of disinfectant towelette products, and that the greater surface area(s) wiped would result in reduced bactericidal efficacy.MethodsThis study tested ten disinfectant towelette products against Staphylococcus aureus strain ATCC CRM-6538 and Pseudomonas aeruginosa strain ATCC 15442 on Formica surfaces. Defined surface areas were wiped and the towelette weighed before and after wiping to determine the amount of liquid released. Bactericidal efficacy testing was also performed after wiping following standard EPA protocols.ResultsWe found that disinfectant product, area of surface wiped, and strain impacted the bactericidal efficacy achieved. Disinfectant product type and area of surface wiped significantly impacted the percent of liquid released per ft2from the towelette.ConclusionOverall, bactericidal efficacy varied by towelette product, surface area wiped, and strain. This study also found that wiping larger surface areas may lead to decreased bactericidal efficacy. Further research is needed to test its implication.

Cross-Contamination by Disinfectant Towelettes Varies by Product Chemistry and Strain

“…Quaternary ammonium towelettes transfer more P. aeruginosa than hydrogen peroxide towelettes Hydrogen peroxide products transferred signi cantly less log 10 CFU/100 cm 2 to previously uncontaminated surfaces than QA products. This is similar to previous ndings by our group where we demonstrated that hydrogen peroxide disinfectant towelettes were more bactericidal against S. aureus and P. aeruginosa inoculated on 97 mm Formica disc than quaternary alcohol towelettes [18]. This signi cant difference could be explained by the potential for accelerated HP products to produce hydroxyl free radicals which are generally more bactericidal than quaternary alcohols [20].…”

“…Regardless of strain, the cross-contamination risk presented by disinfectant towelettes was highly product-dependent as HP3, QA1 and QA3 wipes had signi cantly lower log 10 CFU/100 cm 2 postdisinfection than HP1 and QA2. The observed differences may be explained by factors as differences in the wipe material type [33], active ingredient class [17], and differences in the amount of liquid released onto the test surfaces [18] during the wiping process. The disinfectant towelette substrate type has been demonstrated to play a major role in the physical removal of pathogens from test surfaces [34].…”

“…S. aureus and P. aeruginosa persist on these surfaces [12,13], increasing transmission risk resulting in HAIs [14]. Overall, pathogen persistence could be due to sub-lethal concentrations of disinfectants [15,16], low e cacy levels for some classes of disinfectant wipes [17,18], amount of surface area wiped [18], and the label-use recommendations not being followed [19].…”

Disinfectant Wipes with Nonsporicidal Claims Transfer Clostridioides difficile Spores from Contaminated Surfaces to Uncontaminated Surfaces during the Disinfection Process

“…This was evident as the 0.5 m 2 and 1 m 2 surfaces were visibly wet after the wiping process. In a previous study by our group [22], we found that the percent of liquid released per 0.1 m 2 of a Formica surface significantly decreased as the surface area wiped increased. However, overall, there were no significant differences in the log 10 CFU/100 cm 2 of spores transferred to the 0.5 m 2 1.0 m 2 , 1.5 m 2 and 2.0 m 2 surface areas.…”

“…In addition, the Environmental Protection Agency (EPA) has no recommendation on the maximum surface area that could be disinfected with a towelette in order to optimize bactericidal efficacy, while minimizing the risk of cross-contaminating low risk surfaces. In prior work by our group, we found that the efficacy from pre-wetted disinfectant wipes was related to the ability to keep surfaces wet for the label contact time, so "stretching" a wipe to wipe larger areas than the wipe can disinfectant may create risks of suboptimal disinfection and cross-contamination [22].…”