Contact Lenses & Bacteria

On a day to day basis, our hands come into contact with a germ-infested world. From the dusty seats on the bus to the 10 year old office keyboard at work, harmful bacteria love to linger in unexpected areas that we often neglect or assume to be clean. This is why all our opticians will always remind you to wash your hands thoroughly before handling your contact lenses. But now, in light of recent studies, this golden advice should not be taken lightly at all.

Researchers at the NYU Langone Medical Centre have found data that suggests people that wear contact lenses overall are significantly more likely to develop eye infections than those who do not wear contact lenses. They have found that this is primarily due to changes in the bacteria population in the eye. Bacteria is readily transferred from the fingers to the eyes of contact lenses when the user applies or removes them. The pressure of the contact lenses whilst in the eye also affects the levels of bacteria, allowing them to be trapped and not as easily washed away by the moisture of the eye.

The researchers found that in a sample of 20 people, 9 of the individuals who wore contact lenses daily showed 3 times more bacteria than the 11 people who did not wear contact lenses at all. The bacteria in the eyes of these contact lens wearers were also found to be a lot more varied in strains and population, with bacteria that is usually found on skin being highly prevalent in the eye.

Senior study investigator, Maria Gloria Dominguez-Bello had this to say about the findings: “What we hope our future experiments will show is whether these changes in the eye microbiome of lens wearers are due to fingers touching the eye, or from the lens’s direct pressure affecting and altering the immune system in the eye and what bacteria are suppressed or are allowed to thrive”.

This study is considered to be a preliminary assessment, and hasn’t been published in any peer reviewed journal but key investigator Dominguez-Bello has hopes that it will lead to a better understanding of why contact lens wearers are more prone to eye infections than non-contact lens wearers, and that understanding could lead to better ways of preventing eye infections in the future.

At the moment, it is common practice for all contact lens wearer to keep to the strict hand washing routine to avoid conditions such as Acanthamoeba keratitis. Acanthamoeba keratitis is a rare disease in which amoebae invade the cornea of the eye, that may result in permanent visual impairment or blindness. As this is a rare case conditions such as these should certainly not put you off using contact lenses but do serve as an example of why it is so important to keep a high level of sanitation and hygiene when handling your contact lenses.

Recommendations for handling your contact lenses include:

  • Always wash and dry your hands before handling your contact lenses.
  • Carefully and regularly clean lenses by carefully rubbing the contact lens with your clean finger and rinse them thoroughly before soaking the lenses overnight in multipurpose solution (completely covering the lenses).
  • Always store you lenses in the proper lens care storage case and replace your case every 3 months, maximum!
  • See your optician regularly for your scheduled contact lens and eye examination.

With these four simple steps our opticians guarantee that you will have the best fighting chance in our battle against the germs!