Contact Lens Infections: What You Need to Know

Contact lens wearers, listen up! Although contact lenses are generally safe and comfortable, if you don�t use them properly you may be putting yourself at risk for a number of eye complications, including vision loss. Here are some tips to help prevent infections.

If you wear contact lenses then you know first-hand how convenient they are. After all, they improve vision, are ideal for playing sports and are more enjoyable to wear on a rainy day than glasses ever will be. However, it is important to remember that contact lenses are medical devices that require a high level of care.

When you are first fitted with contact lenses, your eye doctor will show you the proper contact lens cleaning technique � first clean and rinse, then disinfect. Sounds easy, right? But according to Dr. Harold Stein, an ophthalmologist at the Bochner Eye Institute, most contact lens-related infections are a result of poor habits or lens hygiene.

While daily disposable contact lenses � designed to be thrown out after each use � require no cleaning, other types of lenses come with a regular cleaning and disinfecting schedule to prevent discomfort and infections. And all lenses come with usage guidelines as well. Stick by the rules to prevent problems later on.

Case Study: The Nightmare Nap

Just ask Erika Parrales, a 30-year-old contact lens wearer. One day last year, Parrales took a short nap � with her lenses in.

�When I woke up, I noticed my contacts felt extremely dry,� she says. �I tried lubricating them before taking them off, but they felt glued to my eyes.� Nonetheless, she persisted, and finally removed them. �As I was taking them off, it literally felt like I was peeling a layer off my eyes.�

Parrales tried more lubricating drops to ease the stinging sensation she felt once she removed her lenses. Over the next few days, she kept feeling as if she had something in her eye. She thought it might be lint or an eyelash, but there never seemed to be anything causing it. As the days went on, the feeling only became worse. That�s when she sought the attention of her eye doctor, who diagnosed her with Thygeson�s Keratitis, an uncommon, chronic inflammatory condition affecting the front layer of the cornea. She had developed the disease as a result of sleeping with her contacts in, which scratched and scarred her cornea and restricted the oxygen to her eyes.

Parrales�s doctor gave her steroid drops and antibiotics to reduce inflammation and to heal the cornea. Her eyes now feel much better, but she has stopped using her contact lenses as frequently because she no longer tolerates them for long without feeling discomfort. �After wearing contact lenses for 15 years, it took a bit of adjusting to get used to wearing my glasses again,� she says. �I can no longer use my contacts as often as I used to.�

Types of Infection

Most contact lens infections are part of a category of infections called keratitis � an inflammation of the cornea. Keratitis can be caused by trauma to the cornea (such as a scratch caused by your fingernail while taking off or inserting your lenses) or by bacteria or fungus from a dirty lens.

Here are some types of keratitis that affect contact lens wearers:

Amoebic keratitis: A rare but potentially blinding infection caused by a common organism found in tap water, swimming pools, hot tubs, etc.

Bacterial keratitis: An infection caused by bacteria found in soil, water, sewage and plants.

Fungal keratitis: A serious and painful corneal disease caused by a fungal organism.

Corneal ulcer � An open sore in the outer layer of the cornea. Although rare, untreated corneal infections may result in a corneal ulcer and are extremely serious. For more information, see Common Eye Infections.


If you are a contact lens wearer, or are considering becoming one, take note of these tips to reduce your risk of infection:

  • Colour photo of a man inserting contact lenses into his eyeHave regular eye exams. You eye doctor will tell you if you are a good candidate for contact lens wear and will properly fit you for lenses.
  • Wash your hands before handling contact lenses. Bacteria from your day-to-day travels can easily get on your lenses if your hands are not clean.
  • Carefully and regularly clean contact lenses with a lens care solution recommended by your eye doctor. And never re-use old solution.
  • Store lenses in their proper case, and keep it clean. Replace your case every three months or as recommended by your eye doctor.
  • Talk to your eye doctor to determine how often you should be replacing your lenses. If you have daily disposables, for example, be sure to throw them away daily, otherwise you are significantly increasing your risk of infection. Saving money in the short term may lead to vision loss in the long term.
  • Follow the wearing schedule recommended by your eye doctor.
  • Do not sleep with lenses in. It can cause eye irritation, scratches on your corneas or infections from unclean or unsterile lenses. Extended wear lenses still carry the risk of complications, and it is probably better to remove them nightly.
  • Avoid bathing, showering or swimming with contacts in. Bacteria in the water can stick to your lenses and cause serious infections. If it is absolutely necessary to wear your lenses while swimming, wear goggles and disinfect your lenses afterwards.
  • See your eye doctor immediately if you wear contacts and notice eye pain, eye redness, blurred vision, sensitivity to light, excessive tearing or the sensation of having something in your eye.

For more information, see Glasses or Contacts? on CNIB�s website.