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Friday, 28 September 2018

Increase of contact lens related sight threatening eye infection



UCL, University College London alongside Moorfields Eye Hospital led  a study of infection in contact lens wearers. Since 2011, the researchers found three times as many incidences of Acanthamoeba keratitis in South-East England. A rare but preventable cause of blindness.

When contact lens users are aware of the risks involved in poor lens hygiene, they often adopt the correct habits and infection is unlikely. The increased cases illustrates the need for awareness.

Findings published in the British Journal of Ophthalmology, saw reusable contact lens wearers were at the highest risk. This group are more likely to have used ineffective lens solution, have water contaminate their lenses and admitted to poor lens hygiene.



What is Acanthamoeba keratitis (AK)?

  • An eye disease affecting the cornea, the front surface of the eye. 
  • It becomes inflamed and painful due to the infection. 
  • The Acanthamoeba bug forms cysts during infection. 
  • It is not only contact lens wearers that can be infected, but wearers pose a higher risk due to contamination of lens cases. 



What are the statistics?

  • It can affect 2.5 in every 100,000 contact lens wearers.
  • 25% of people with AK need corneal transplants to treat the disease or restore vision. 
  • A quarter of affected patients become severe cases, loosing up to 75% of their vision or going blind all together. 
  • Since 2000 - 2003 where incidences were 8-10 in a year, it's now noted that we treat between 36-65 cases annually.

What increases the risk?

  • Researchers found that people were three times more likely to contract AK, if they had poor contact lens hygiene. 
  • Those who did not consistently wash and dry their hands as part of their lens routine. 
  • Also, in people who wore their contact lenses swimming or in hot tubs, while showering or face washing.



Where is Acanthamoeba found?

  • The Acanthamoeba bacteria is actually found in the UK more commonly than in other countries. 
  • Water contamination is the main concern for the UK, as Acanthamoeba is found in higher levels in domestic water supplies, as opposed to mains water. 
  • As well as hot and cold water, it can also be found in soil.



How can I prevent an AK infection?

  • Always follow your Optometrists advice on good lens hygiene and best practice.
  • Wash and completely dry your hands before handling your lenses. 
  • Avoid wearing your lenses swimming, when washing your face or showering/bathing. 
  • Consider switching to a daily disposable lens, you can ask your optometrist to check your suitability and which lens type would be best for you. As the lens is replaced each day, there is no feeding ground for bacteria to grow over time and each lens is clean and fresh.


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