Here's why contact lenses can be harmful for eye health

Listen up contact lens lovers! A new study has found that wearing lenses can cause more infections in your eyes as compared to those who don't wear them.

Researchers at NYU Langone Medical Center used high-precision genetic tests to differentiate the thousands of bacteria that make up the human microbiome, and found a diverse set of microorganisms in the eyes of daily that more closely resembles the group of microorganisms of their eyelid skin than the bacterial grouping typically found in the eyes of non-wearers.

Specifically, the NYU Langone team found that the eye surface, or conjunctiva, has surprisingly higher bacterial diversity than the skin directly beneath the eye and three times the usual proportion of Methylobacterium, Lactobacillus, Acinetobacter, and Pseudomonas bacteria in the eyes of the study's nine contact lens wearers than is typically found on the surface of the eyeballs of 11 other men and women in the study who did not wear contact lenses.

When measured and plotted on a graph, statistical germ diversity scores showed that the eye microbiome of contact lens wearers had a composition more similar to that of the wearer's skin than the eye microbiome of non-lens wearers.

Surprisingly, more Staphylococcus Bacteria, which are linked to eye infections and more prominent on the skin - were found in the eyes of non-lens wearers, and researchers do not yet have an explanation for the disparity. Estimates vary, but many cases of potentially scarring bacterial keratitis, or eye inflammation, as well as conjunctival infections occur in contact lens wearers.

Senior study investigator and associate professor Maria Gloria Dominguez-Bello, PhD said that they still had to figure if these changes were 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.

The report was presented at the annual meeting of the American Society for Microbiology in New Orleans.