Biofilm and Contact Lens Cases

Lens case hygiene practices are important in maintaining safe contact lens wear. Current multipurpose disinfecting solutions may not be effective against the biofilm forms of bacteria.

Biofilm is a group of microorganisms that are joined together on a surface such as inside contact lens storage cases, and even in your dog’s water dish.

These microorganisms adhere to each other with molecular strands called extracellular polymeric substances, or EPS.

Biofilms are diverse communities of bacteria and other microorganisms. They form primarily in moist environments or those that are conducive to bacterial growth, such as metals, plastics and medical equipment.

While a single type of organism can create a biofilm, naturally occurring biofilms are commonly made up of many different types of bacteria, fungi, algae, yeasts and other micoorganisms.

Dental plaque and the build-up found in clogged drains are common examples of biofilm, as is that sticky film in the bottom of your dog’s water dish.

A recent epidemiologic study has confirmed that poor lens case hygiene is strongly associated with contact lens–related corneal infections and other ocular complications. It is important therefore that contact lens wearers perform effective lens case hygiene practice to minimize lens case contamination. Lens case contamination is frequent in the contact lens wearing population, and the lens case is often the most contaminated lens accessory item. Recommended hygiene practices do not necessarily ensure a lens case free of contamination. Factors such as biofilm formation and inherent microbial resistance may be associated with persistent microbial contamination of contact lens storage cases – therefore it is recommended that you replace your lens case about every three months.

Current multipurpose disinfecting solutions may not be effective against the biofilm forms of bacteria so we suggest you replace your case several times per year.