Contact Lenses Lower Immunity by Impairing Eye Microbial Colonies, Study

Wearing contact lenses may change the community of bacteria living in your eyes, found a small, new study, according to livescience.

The study revealed that the surface of the eye in the people who wore contact lenses had triple the proportion of certain bacteria species on average, compared with people in the study who did not wear the lenses, said the researchers.

The results of the study were revealed at the annual meeting of the American Society for Microbiology in New Orleans.

The researchers also found differences in the bacterial community on the surface of people's eyes. Those who wore contact lenses had a bacterial composition that was most like the bacteria on their eyelids, in contrast to the non-wearers. The study thus included nine people who wore contacts as opposed to 11 who did not.

"Our research clearly shows that putting a foreign object, such as a contact lens, on the eye is not a neutral act," study author Maria Gloria Dominguez-Bello, a microbiologist at NYU Langone Medical Center, said.

Thus, more research can show whether the alterations in eye bacteria are due to fingers touching the eye, or due to contact lenses altering the immune system in the eye. It might resolve "the long-standing problem of why contact-lens wearers are more prone to eye infections than non-lens wearers," Dominguez-Bello said.

Since the introduction of soft contact lenses in the 1970s, there has been an increase in the prevalence of corneal ulcers, or sores on the transparent covering of the eye, study co-author Dr. Jack Dodick, a professor and chair of ophthalmology at NYU Langone, said.

Pseudomonas is a type of bacteria that leads to corneal ulcers, and spreads quickly in the eyes of people who wore contacts. As the bacteria could transfer easily to the eyes from the skin, eyelid and hand, hygiene should be given a lot of attention in order to avoid getting corneal ulcers, Dodick said.

A number of studies can reveal how exactly such differences in bacterial composition impacts the health of the eyes, said the researchers.

Fromer said that some simple steps can help to prevent bacterial transferences. "Wash your hands, change your lens solution every day, keep your lens case clean," he said. The same lenses should not be worn regularly, he added.

Ophthalmologists should be visited regularly, Fromer said. "If something does not feel right, it means that it is not right," he said.