Evaluation of organic load-related efficacy changes in antiseptic solutions used in hospitals.

BACKGROUND: In this study, it was aimed to evaluate the change in antimicrobial efficacy related to the presence of the organic load of four different antiseptic solutions that are frequently used in hospitals. METHODS: Solutions of hydrogen peroxide, povidone-iodine, chlorhexidine digluconate, and ethyl alcohol were prepared, tested in terms of antimicrobial efficacy changes in the presence of organic substances, and evaluated according to EN 13727 and EN 13624 standards. RESULTS: Among the investigated solutions ethanol 70% solution showed the best results by providing a 5-log reduction on all test organisms without affecting by the type and concentration of organic substances. Solutions of hydrogen peroxide 3%, povidone-iodine 7.5%, and chlorhexidine digluconate 0.2% performed lower antimicrobial efficacy depending on the concentration of organic load. DISCUSSION: It is concluded that the antimicrobial efficacy of antiseptic solutions is significantly affected by the organic substances and thus the proper use of antiseptics has become important to achieve successful disinfection and prevention of antibacterial resistance.

Comparison of bactericidal and fungicidal efficacy of antiseptic formulations according to EN 13727 and EN 13624 standards

Background/aim: In this study, the antibacterial and antifungal properties of the five most commonly used antiseptic formulations were evaluated in terms of different contact times and organic conditions. Materials and methods: Solutions of chlorhexidine digluconate, povidone iodine, isopropyl alcohol, hydrogen peroxide, and tincture of iodine were prepared and tested according to European standards EN 13727 and EN 13624 with different parameters. Results: The results showed that isopropyl alcohol (70% v/v) and tincture of iodine (2%) had greater bactericidal and fungicidal activity against the four tested bacteria and two fungi in all conditions. Conclusion: When the results of the five different active substances were quantitatively evaluated regarding their bactericidal and fun-gicidal activities, it was found that contact time and organic load significantly affected the antiseptic efficacy.

Efficacy of octenidine- and chlorhexidine-based wash-mitts against Candida albicans and Candida auris - a comparative study.

BACKGROUND: Management of outbreaks of the newly emerging pathogen Candida auris may include use of antimicrobial wash-mitts for decolonization. However, currently there is little clinical evidence to support the wide adoption of 'whole-body decolonization' as part of the protocol to effectively manage C. auris outbreaks. The aim of this study was to investigate the chemical tolerance of C. auris compared with the surrogate test organism Candida albicans as established in the European Standards (EN). METHODS: Two commercially available antiseptic-impregnated wash-mitts based on either chlorhexidine digluconate (CHG) or octenidine dihydrochloride (OCT) were studied. Comparison of susceptibility of C. auris and C. albicans was investigated based on the standardized test protocol EN 13624. Experiments were conducted using the impregnation liquid squeezed from the wash-mitts at a contact time of 30 s at different concentrations between 0.5% and 97% in the presence of low organic soiling. FINDINGS: Yeasticidal efficacy according to EN 13624 was found for the OCT wash-mitts at 30 s at ≥10% concentration with C. albicans. In comparison, reduction ≥4 log10 was found at a much lower concentration of ≥1% for both C. auris strains. For the CHG wash-mitts, efficacy against C. albicans was below 2 log10 reduction at 97% concentration within 30 s. Efficacy against the two C. auris strains was around 3 log10 reduction. CONCLUSION: Both C. auris strains were found to be significantly more susceptible when compared with C. albicans. Data also demonstrate that not all antiseptic-impregnated wash-mitts are equally effective against C. auris with OCT having a higher efficacy compared with CHG.

Investigation of the susceptibility of Candida auris and Candida albicans to chemical disinfectants using European Standards EN 13624 and EN 16615.

BACKGROUND: Since the first appearance of Candida auris in 2009, this yeast has become a relevant pathogen in the clinical field. C. auris has been detected on various surfaces in health facilities, and is therefore a target for appropriate disinfection procedures. Preventive measures have to be implemented based on disinfectants with proven efficacy against C. auris. AIM: The chemical tolerance of C. auris was compared with the surrogate test organism Candida albicans as established in the European standards (EN). In this way, conclusions will be drawn as to whether the disinfectants tested according to EN 13624 and EN 16615 are at least equally effective against C. auris. METHODS: The chemical susceptibility of C. auris and C. albicans was investigated using standardized EN test protocols. EN 13624 and EN 16615 were used in this study to examine two commercially available surface disinfectants based on alcohol and quaternary ammonium compounds (QACs), respectively. In addition, the survival rates of the two yeast species were studied on a defined test surface simulating practical conditions. FINDINGS: In comparison with C. albicans, C. auris was found to be significantly more susceptible to the alcohol- and QAC-based disinfectants used in this study. C. albicans was found to be more tolerant to drying on the test surface in EN 16615, yielding higher recovery rates. CONCLUSION: C. albicans is a suitable surrogate test organism when targeting yeasticidal efficacy, which, based on EN 13624 and EN 16615, includes efficacy against the human pathogen C. auris.