Eye Infections

When harmful micro-organisms invade any part of the eyeball or surrounding area, the resulting condition is an eye infection. Areas of the eye that are most commonly affected include the cornea, which is the clear front area of the eye, and the conjunctiva, which is the thin, moist membrane lining of the outer eye and inner eyelids.


Man with Pinkeye

Symptoms include pain, eye discharge, red eyes, swollen and watery eyes, itching, light sensitivity, swelling, and/or blurred vision. If you suspect you have an eye infection, you should visit your eye doctor right away. Delays can exacerbate the situation and potentially harm your sight. If you wear contacts, switch to glasses until a diagnosis and treatment for your condition begins, or your eye doctor tells you otherwise.

There are many different types of infections. Your doctor may take a sample from your eye to help determine the type of infection in order to best treat and target the condition.

Causes and Types

Infections tend to be viral, bacterial or fungal in nature.

Pink eye, or conjunctivitis, is a viral or bacterial infection that is highly contagious and often found in young children. Infants can also acquire conjunctivitis during birth if the mother has a sexually transmitted disease.

Another viral eye infection is viral keratitis, which happens with exposure to the herpes simplex virus.

Fungal keratitis results when a fungi invades the eye. Acanthamoeba keratitis are a parasite that could invade the eye.

Less common in the US is trachoma, which in under-developed regions is the leading cause of blindness. The infection is spread by flies, and the risk of reinfection is high. The affected typically is infected at the inner eyelid, which scars and causes the eyelid to have an “in-turning,” pointing the eyelashes towards the cornea where constant brushing and agitation eventually leads to blindness.

Bacterial endophthalmitis occurs when an eye infection penetrates to the inner eye. Without immediate treatment, the infection could result in blindness. This type of infection can be caused by a penetrating injury or rarely as a complication of eye surgery. In very rare cases, mold that penetrates the eye’s interior also causes endophthalmitis. Most of these cases occur in the tropics area.

Note that Your risk of eye infections increases if you wear contact lenses. It is important if you wear contacts to observe certain safety precautions. Avoid swimming in your contacts, or remove and disinfect immediately afterwards.


An infection could result in a stye (a sort of pimple on the eyelid) or chalazion (a benign bump or nodule) on the interior portions of the upper and lower eyelid. If an infection reaches the tear glands, inflammation can result. Infections can also potentially block an eye’s drainage system, causing dacryocystisis. Corneal ulcers are sometimes caused by infections, and can result in severe vision loss if left untreated.


Most bacterial infections clear up with time, especially with prompt treatment of antibiotic eye drops, ointments, or compresses. Common viral infections tend to clear up on their own. If the infection is severe, antiviral eye drops may be prescribed. Sometimes anti-inflammatory eye drops are necessary to regulate the symptoms of a viral infection.

Depending on the severity of your infection, additional oral antibiotics may be prescribed. It is key to keep your doctor informed, and if symptoms worsen or change to seek medical help immediately.

Preventing Eye Infections

Person Washing Hands

If someone near you has red eye, make sure to avoid contact with your own eye until you wash your hands. Most anti-infective sprays and cleaners are effective at helping to mitigate the spread of infections. Be conscious if you work in or visit public areas such as day care centers or classrooms.

If someone in the household has an eye infection, help them keep their bedding and towels clean, and don’t let them share with other family members. Remind them to wash their hands often.

Good hygiene starts young. Teach and remind your children to wash their hands often and thoroughly.

If you wear contacts, make sure to follow safety tips and be vigilant about hygiene. Only handle contacts with clean hands. Sleeping with contact lenses, even with new high-oxygen flow lenses that are FDA approved for overnight wear, will still increase your risk for infection.