CL wear changes eye bacteria and may increase infections

Contact lens wearers have different bacteria living on their eyes compared to non-wearers, which may increase the risk of eye infections

contact lenses bacteria infection

The increased occurrence of eye infections in contact lens wearers could be explained by differences to the bacterial colonies living on the surface of the eye, compared to non-wearers, according to new research.

The findings were presented at the annual meeting of the American Society of Microbiology in New Orleans last week (May 31).

A small US study found a number of differences between the bacterial colonies on the surface of the eyes in contact lens wearers compared with non contact lens wearers, with the surface microflora of lens wearers found to more closely resemble the skin of the eyelid than the eyes of non-wearers.

A team of researchers from the NYU Langone Medical Center in New York swabbed the eyes of nine contact lens wearers and 11 non-wearers, and found increased prevalence of a number of bacteria species, including Methylobacterium, Lactobacillus, Acinetobacter and Pseudomonas on the surface of the eyes of contact lens wearers.

Senior study investigator, microbiologist Dr Maria Gloria Dominguez-Bello, said: “Our research clearly shows that putting a foreign object, such as a contact lens, on the eye is not a neutral act.”

She added: “These findings should help scientists better understand the longstanding problem of why contact-lens wearers are more prone to eye infections than non-lens wearers.”

However, greater amounts of Staphyloccocus were found on the ocular surface of non-contact wearers. The researchers are unable to account for how this family of bacteria, which are linked with eye infections such as conjunctivitis and keratitis, are more prevalent in non-contact lens wearers.

Image credit: National Institute of Allergy and Infectious Diseases (NIAID)