The antimicrobial efficiencies of contact lens solutions

Abstract

Abstract The antimicrobial efficiencies of 34 commercially available contact lens solutions has been tested against Pseudomonas aeruginosa, Staphylococcus aureus, Micrococcus luteus and Candida albicans. A standard inoculum of 106 organisms ml−1 was placed in a sample of a contact lens solution and samples taken at various times up to 48 h. These were placed in a recovery medium and the presence or absence of growth noted after 48 h incubation at 37°. Of 14 solutions used to soak and disinfect lenses only 4 inactivated all four test strains within 1 h, 7 within 4 h, while 6 solutions allowed growth of one or more test organisms even after 24 h contact. Of the remaining 20 solutions, with their various functions such as cleaning and wetting of lenses, 13 failed to inhibit one or more test strains after 24 h contact. Some form of control of the manufacture and presentation together with minimum standards of antimicrobial efficiency would seem to be desirable.