An outbreak of a rare but preventable eye infection that can cause blindness, has been identified in contact lens wearers
A threefold increase in Acanthamoeba keratitis, a preventable eye infection that can cause blindness in contact lens wearers have been reported in this new study from South-east England.
Reusable contact lens wearers with the eye infection are more likely to have used an ineffective contact lens solution, have contaminated their lenses with water or reported poor contact lens hygiene, according to the findings published in the British Journal of Ophthalmology.
This increase in cases highlights the need for contact lens users to be aware of the risks
Acanthamoeba keratitis is an eye disease that causes the eye to become painful and inflamed due to infection by Acanthamoeba. One in four patients have less than 25% of vision or become blind following the disease and face prolonged treatment. Overall 25% of people affected require corneal transplants to treat the disease or restore vision.
The researchers collected data from Moorfields Eye Hospital, from 1985 to 2016. They found an increase in cases from 2000-2003, when there were eight to 10 cases per year, rising to 36-65 annual cases in the past few years.
“This increase in cases highlights the need for contact lens users to be aware of the risks,” said the study’s lead author, Professor John Dart of UCL Institute of Ophthalmology and Moorfields Eye Hospital NHS Foundation Trust.
The researchers conducted a case-control study which included 63 people with Acanthamoeba keratitis and 213 without it, in people who wear reusable contact lenses and who had come to Moorfields emergency department between 2011 to 2014. They all completed a questionnaire, from which the researchers found that the risk of developing the disease was more than three times greater amongst people with poor contact lens hygiene. Risk was also increased in people who used an ineffective contact lens solution, and for people who wore their contacts while in swimming pools or hot tubs. Showering and face washing while wearing contact lenses are also likely to be risk factors.
“People who wear reusable contact lenses need to make sure they thoroughly wash and dry their hands before handling contact lenses, and avoid wearing them while swimming, face washing or bathing,” said Professor Dart.