Purchase this article with an account.
Brien C David, Deborah McGrath, Denise Callahan, Juliann Mason, Julie Bair, Tiffany Hilfiker, Patricia A Walsh, R&D Microbiology; Biocidal Efficacy of Hydrogen Peroxide Solutions Against Clinical Isolates of Fungal Pathogens. Invest. Ophthalmol. Vis. Sci. 2014;55(13):6046.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
: The biocidal efficacy of two hydrogen peroxide solutions were evaluated against clinical isolates of fungal pathogens that have been associated with contact lens related microbial keratitis, including multiple strains of Candida albicans, Candida tropicalis, Fusarium oxysporum, Fusarium solani, and Aspergillus fumigatus.
Testing was performed on two peroxides, a novel peroxide and Clear Care to evaluate biocidal efficacy according to ISO standard 14729:2001/(Amendment 1):2010(E), modified to include organic soil in the preparation of the clinical isolates plus measurement of biocidal activity only at the minimum recommended disinfection time point for each product. Challenge organisms had been isolated from clinical sources. Clinical isolates were prepared by using ~5 X 105 colony forming units (CFU)/mL as the challenge inoculum for separate tests on each solution. Three separate lots, all within expiry, of each solution were tested against each isolate. ISO 14729 primary acceptance criteria (minimum 1.0 log reduction for yeasts and molds to achieve primary acceptance criteria) was used as a guide for evaluating efficacy in this non-compendial testing against the challenge organisms.
Biocidal efficacy results for both peroxides ranged from an approximate 1.0 log reduction from initial challenge levels against certain isolates to > 5.0 log reduction for other isolates.. Both hydrogen peroxide solutions showed efficacy (>1.0 log reductions) for all 24 organisms. The mean log reduction for both peroxides was similar for each solution. The mean log reduction for Clear Care ranged from 1.1 - 5.0 while the novel peroxide solution showed ranges from 1.3 - 5.1 against these fungal isolates. On average, there were no differences.
The results show that the novel peroxide and Clear Care demonstrated in vitro efficacy against fungal species that have been associated with fungal keratitis. The use of methodology based on a modification of the ISO 14729 standard provides data that are easily understood and can be used to characterize the biocidal efficacy of peroxides. Further study is warranted to assess the potential clinical significance of these in vitro results.
This PDF is available to Subscribers Only