Efficacy of MeniCare Soft against Acanthamoeba and Viruses

Simon Kilvington Department of Infection, Immunity & Inflammation, University of Leicester, Leicester, UK

Abstract

The efficacy of MeniCare Soft (Menicon Co., Ltd, Japan), a multipurpose contact lens disinfectant solution, against the pathogenic free-living amoeba Acanthamoeba and the viral pathogens Herpes simplex virus, Poliovirus and Adenovirus was investigated. Assays were developed to test the biocidal efficacy and also the ability to remove adherent organisms from soft contact lenses in “Rub & Rinse” or “No Rub & Rinse” procedures. In the biocidal tests, the solution was active against Acanthamoeba trophozoites giving a 3 - 4 log reduction (99.9 – 99.99% killing) after 4-6 hr. For the cysts, a 3 log reduction was found for A. polyphaga and 1.3 – 3.4 log for A. castellanii after 4-6 hr. For the viruses, ≤1 log reduction occurred after 24 hr exposure. The “Rub & Rinse” or “No Rub & Rinse” procedures resulted in a 4 - 5 log removal of Acanthamoeba and viruses from the lenses. In conclusion, MeniCare Soft was shown to have good disinfectant activity against Acanthamoeba and was also effective in removing trophozoites, cysts and viruses from soft contact lenses.