Researchers Find Three Common Habits That Increase Bacterial Contamination in Contact Lens Cases

contactlensesContact lenses are one of the most popular options for those with poor vision, but according to the findings of a recent study, these lenses can quickly turn into breeding grounds for bacteria — more so than most contact lens wearers realize.

The data was recently published in the February issue of Optometry and Vision Science, which is the official journal of the American Academy of Optometry.

The research team behind the study, comprised of a group of optometrists and eye health specialists from the University of New South Wales, Sydney, focused on common cleaning practices of contact lens wearers and how proper hygiene — or lack thereof — is directly connected to the contamination of lens cases and subsequent vision problems, such as infections.

The research team found that the number of contaminated lens cases was extremely high: positive test results for bacterial or fungal contamination were found in 66% of the lens cases tested, and 40% of those contaminated lens cases had multiple bacterial strains.

In the study, which examined the contact lens hygiene habits of 119 patients, it was revealed that three specific habits contribute to increased contamination of lens cases:

  • Neglecting to wash hands with water and soap (although contamination is less likely for patients who wash their hands with tap water than those who don’t wash their hands at all);

  • Not allowing the lens case to air-dry when the lenses are being worn;

  • Using lens cases and disinfecting solutions that are produced by different manufacturers.

Additionally, the research team found that lens case contamination was more prevalent in patients who had worn contact lenses for two years or more. As a recent article in Infection Control Today explains, “more-experienced wearers may become ‘less vigilant’ with hygiene habits over time.”

The importance of lens case cleanliness is incredibly important, the research team notes, and although microbacterial strains can appear just from handling a lens case, there are simple ways that the wearer can reduce the risk of serious bacterial growth and eye infections. These strategies include letting the lens case dry face-down, not using the fingers to wipe out the interior of the case, and switching to a new lens case every time a new bottle of disinfecting solution is opened.