Basics of Fungal Keratitis

What is fungal keratitis?

 

the fungus Fusarium viewed under a microscope.

Microscopic image of Fusarium, a fungus that causes eye infections

Fungal keratitis is an infection of the cornea (the clear dome covering the colored part of the eye) that is caused by a fungus. Some fungi that can cause fungal keratitis include:1

What are symptoms of fungal keratitis?

Symptoms of fungal keratitis include:

  • Eye pain
  • Eye redness
  • Blurred vision
  • Sensitivity to light
  • Excessive tearing
  • Eye discharge

If you experience any of these symptoms, remove your contact lenses (if you wear them). Call your eye doctor right away if symptoms persist. Fungal keratitis is a very rare condition, but if left untreated, it can become serious and result in vision loss or blindness.

Where are these fungi found?

Fusarium and Aspergillus species live in the environment.2 Candida species normally live on human skin and on mucous membranes (for example, the lining of the eyes, nose, or mouth). Fungal keratitis is most common in tropical and subtropical regions of the world but can also occur in areas of the world with milder temperatures.3 It cannot be spread from person to person.

What puts people at risk for fungal keratitis?

Risks for developing fungal keratitis include2

  • Recent eye trauma, particularly involving plants (for example, thorns or sticks)
  • Underlying eye disease
  • Weakened immune system
  • Contact lens use

In 2006, CDC investigated an outbreak of Fusarium keratitis. The infections were associated with a specific type of contact lens solution, which was withdrawn from the market.4-6

How is fungal keratitis diagnosed?

Your eye doctor will examine your eye and may possibly take a tiny scraping of your cornea. The sample will be sent to a laboratory to be analyzed.

How is fungal keratitis treated?

Fungal keratitis must be treated with prescription antifungal medicine for several months. Patients who do not get better with antifungal eye drops and oral medications may require surgery, including a cornea transplant.2

How do you prevent fungal keratitis?

Wear protective eyewear when performing tasks that may put you at risk for eye trauma involving plants, such as agricultural work.

Follow these tips to keep your eyes healthy while wearing contact lenses.

For more information and additional resources, visit CDC’s Fungal Eye Infections website.

Page last reviewed: February 14, 2022