Common Eye Infections: Signs, Symptoms, Treatment

Written By: Susannah Lockett

Eye infections occur when the eye’s defense mechanisms fail and bacteria, mold, or viruses invade the eye. The eye’s tear system normally protects the eye and usually does a remarkable job, considering the eyes’ open exposure to the air.

Any part of the eye can become infected, including the cornea, the conjunctiva and white part of the eye, the inner eye structures, the eyelids, and the tear duct system. Many eye infections clear on their own and require no treatment beyond simple comfort measures that your eye doctor may recommend.

It’s uncommon, but certain eye infections can threaten vision.

Symptoms of an Eye Infection

These may be related to the primary infection cause and may include:

1. Redness

2. Eye pain

3. Dry or watery eyes

4. Itching and swelling around the eyes

5. Blurry vision

6. Light sensitivity

7. Swelling of the eyes

If you suspect an eye infection, contact your eye doctor immediately. If you wear contacts, remove them right away and wear your eyeglasses until your eye doctor says it’s safe to wear contacts again.

If you don’t use daily disposable lenses, you should discard lenses worn during an active eye infection.

Eye Infections: Causes and Types

A very common eye infection is known as conjunctivitis. It affects the conjunctiva, the membrane lining the whites of your eyes, and also the inside of the eyelids. It’s called pink eye due to the inflammation of the conjunctiva’s blood vessels, which turns the whites of the eyes a pinky reddish color.

Pink eye thrives in crowded environments with poor hygiene or small children who don’t understand handwashing. The condition can burn through a preschool or elementary school in no time. It’s highly contagious, and the viral form can also spread through the air with uncovered coughs and sneezes.

Teachers and child care workers are at an elevated risk of conjunctivitis.

Eye infections can be transmitted to a newborn during vaginal childbirth if the mother has an active gonorrheal or chlamydial infection. If this is the case, delivery by cesarean section will protect the child’s eyes.

Viruses in the herpes simplex family, which cause cold sores and genital lesions, can also infect the eyes.

Cats are prone to herpes infections of the eyes. These rarely cause eye damage but can be very uncomfortable for the animal and are easily passed from cat to cat.

Herpes viruses cannot pass from cat to human or vice versa.


This is a localized infection of a tiny gland along the eyelid’s edge. It’s similar to a boil and looks like a big red pimple. The infection is bacterial and typically goes away on its own. A stye can be very uncomfortable. Home remedies like warm compresses may ease discomfort and speed healing.

A chalazion looks like a stye but isn’t. It’s caused by a blockage of the oil glands in the eyelid but is not bacterial. Chalazions are not painful.


Acanthamoeba keratitis

This microbe lives in tap and bottled water and is ordinarily harmless if ingested orally. However, a severe infection can result if water heavily infested with this amoeba gets in the eyes.

Wearing contact lenses increases the risk for acanthamoeba keratitis significantly. You can minimize this by following your eye doctor’s instructions for contact lens care. Daily disposable lenses will further decrease your risk.

Don’t swim or shower with contact lenses in. This may trap microbes against your eye and cause an infection that would otherwise not occur. Never rinse your lenses with tap or bottled water. Use the contact lens care solution recommended and approved by your eye doctor.

Never use expired lens solution or expired daily disposable lenses. Even though these items may be sealed, contamination can still result if the product is too old.


This one is also gravely serious and can cause vision loss and blindness without immediate treatment. This is mainly because this infection invades the inner eye structures. The medical term “endo” means “from within.”

Endophthalmitis can occur after a penetrating eye injury or as a rare complication of eye surgery. There is about a 4 to 8 percent chance of this condition after a penetrating eye injury.

Mold can also cause endophthalmitis, but this is typically seen in tropical regions.

Fungal keratitis

The fungi Fusarium is often found outside in organic matter. A related injury could transmit it, such as being slapped in the eye by a swinging tree branch. In 2006, a certain brand of contact lens solution was found responsible for a Fusarium outbreak.

That brand of solution is no longer on the market.


It’s not much of a threat in the United States, but in other parts of the world, this bacterial infection caused by Chlamydia trachomatis has blinded or visually impaired about 1.9 million people.

Worldwide, it’s the leading cause of blindness caused by infection. Highly contagious trachoma is spread through infected personal items and bacteria-carrying flies landing on the nose and eyes.

Eye damage is from scarred eyelids that turn inwards, causing the lashes to rub against the cornea and damage it. It’s treatable if caught early with antibiotics and partially preventable with good hygiene and insect abatement programs.

Eye Infection Complications

Eye infections can progress to cause serious eye damage. Infected tear ducts can cause blockage of the tear drainage system and uveitis, an inflammation of the eye’s inner structures.

Infections can also cause a corneal ulcer, resulting in severe vision loss if left untreated. Serious eye infections can invade the eye’s interior and threaten vision.

Orbital cellulitis, an infection of the eyelids, is a medical emergency because treatment must start before the infection spreads further.


Your doctor may need to know what kind of organism is causing your eye infection. To do this, your doctor may take a sample from the infected area and send it to a lab for identification. From there, you may be started on an antibiotic designed to treat that particular microbe.

Viral infections typically clear without treatment, but some may require antiviral eye drops to fight the virus. A steroid eye drop preparation may also be prescribed to reduce inflammation.

Prescription treatment typically involves medicated drops or ointment. Eye compresses may help to ease symptoms while the infection heals.

Preventing Eye Infections

Be aware of others around you. If someone has red, swollen eyes, avoid them and wash your hands as soon as possible. Do not touch your face or eyes until you’ve had a chance to scrub your hands with warm water and soap for at least 20 seconds.

Teach children to avoid touching their faces with unwashed hands. You can carry antibacterial sprays to use in public places. At home, disinfect doorknobs, faucets, and telephones with wipes or solutions meant to kill germs.

If a family member has an eye infection, keep their towels and pillowcases separate. Launder them in hot water before reuse. Bleach is an excellent disinfectant. Teach all household members to wash their hands regularly.

If you wear contacts, wash your hands before caring for them and use approved methods to clean and store them. Daily disposables pose the least risk for infection. If you sleep in contact lenses, even those intended for that purpose, you will significantly increase your infection risk.

Find a Top Eye Doctor Near You

We want everyone to have a regular eye doctor. We promote annual eye exams and work with top-rated eye doctors across the country.

We’ll ask you some questions and then match you to a great eye doctor near you. We can also answer your questions about the doctor and what to expect during your exam. If you prefer, we can set your appointment with your new eye doctor as well. We make the process very easy for you, and we look forward to hearing from you.

Published on: Apr 27, 2022
Last Updated:
Latest Articles