Posted on February 17, 2016
A concise communication recently published in the Infection Control & Hospital Epidemiology (ICHE) journal¹ provides effectiveness data on a novel formulation of ethanol used for glove decontamination to prevent Clostridium difficile (spores) hand contamination during glove removal. Inoculum of 1 x 10? log spores of C. difficile was placed on the gloved hands of each volunteer and rubbed to cover the entire surface of the gloves until dry.
Test solutions included the novel, sporicidal ethanol formulation (70% ethanol adjusted to pH 1.3 with hydrochloric acid), as well as, 1:10 and 1:100 dilutions of sodium hypochlorite (bleach), and 70% ethanol with no pH adjustment/additives. These test solutions were applied for 30 seconds and then cultured on C. difficile selective media. The log-10 colony forming unit of spores was calculated by subtracting spore counts recovered from treated gloves from the counts recovered from untreated control gloves. This study was performed in triplicate and a one-way analysis of variance with Tukey correction was used to compare log reductions.
The study found that the novel, sporicidal ethanol formulation was effective in rapidly reducing C. difficile spores by approximately two logs, with a further reduction when applied as a wipe. The reduction achieved by the sporicidal ethanol was equivalent to the 1:100 dilution of bleach solution. In USP Chapter 797, both its current version and proposed revised version, require periodic glove disinfection between procedures while compounding sterile preparations or when in contact with non-sterile surfaces using sterile 70% isopropyl alcohol (IPA). Typically the application of 70% IPA is by aerosol spray, not wipes. It is common knowledge that 70% IPA is not sporicidal, so would this novel, sporicidal ethanol formulation be a better alternative for routine glove decontamination in the pharmacy?
The researchers state that they are investigating formulations with pH 3.5 that they anticipate will be safer if repeated skin exposure should occur. Furthermore, any gloves subjected to such disinfection should be assessed for chemical compatibility with repeated exposure to this sporicidal ethanol formulation. In my opinion, this novel glove decontamination strategy warrants further study from the pharmaceutical sterile compounding perspective.