Eye infection is a blanket term for a lot of different problems caused usually by bacteria or viruses getting into the eye or eyelid. Eye infections may affect both eyes or just one. They may show up in different parts of the eye, such as the cornea, eyelid or conjunctiva (the thin covering of the inside of your eyelid and surface of your eye). Eye infections are common worldwide both in people who wear prescription eyeglasses and those who don’t.

How dangerous are eye infections?

Depending on the type of infection, the answer to this question can vary wildly. Some eye infections are mostly harmless nuisances that go away on their own, while others can compromise your vision or even result in permanent eye damage. It is important to always consult with an eye doctor to rule out the possibility of a dangerous or damaging infection. As a general rule, the deeper within your eye the infection is set, the more dangerous it is.

Symptoms of eye infections

If you find your prescription glasses suddenly no longer work right, or your eyes have become so light sensitive that you’re living in sunglasses, it may be signs of an eye infection. Eye infections can manifest with a lot of different symptoms, often in conjunction, such as:

  • Pain or discomfort
  • Redness
  • Watery eyes or discharge
  • Dry eyes
  • Sensitivity to light
  • Swelling or itching
  • Blurry vision

Which eye infections are most common?

There are many types of eye infections, some more likely than others. Fungal eye infections, for example, are very rare, though they can be extremely serious when they do occur. Infections from bacteria and viruses are the most common.

  • Conjunctivitis

Possibly the most common eye infection. Conjunctivitis is marked by red, sticky or watery eyes and is rarely dangerous. It may be treated with antibiotics if it is serious enough.

  • Stye

Styes are caused by a bacterial infection taking hold in the follicle of the eyelash. The skin near the base of the eyelash will flare up into a red, painful lump.

  • Keratitis

A common infection of the cornea typical of contact wearers. A rarer form of keratitis, called acanthamoeba keratitis, can be extremely serious and cause vision loss or even total blindness. Acanthamoeba keratitis is on the rise globally, and proper contact lens care remains the best preventative measure.

  • Blepharitis

This common infection is caused by bacterium or parasites and typically results in swelling of the edge of the eyelids and sometimes redness of the eyes.

What causes common eye infections?

Infections are born from bacteria, viruses, fungus and other microorganisms that don’t belong inside your eye. But oftentimes the infection only takes hold due to behaviors, injuries or underlying diseases that give it ample opportunity to take hold.

Contamination is one of the most common causes of eye infections. Throughout your day, your hands pick up millions of germs and can easily pass these onto the surface of your eye. So try to avoid touching your eyes and the skin around them at all costs. If something gets into your eye, don’t rub at it. Doing so will only increase your odds of developing an eye infection.

Improper contact lens care is another cause of many eye infections. As a general rule, contact lenses should not be worn while you swim, shower or use a hot tub because of the increased likelihood that bacteria from the water will end up trapped beneath the lens. Not following contact lens cleaning instructions (for both the lenses and the case) is also frequently to blame for bacterial eye infections. Those who use prescription eyeglasses over contact lenses may be less likely to develop eye infections.

People with compromised immune systems are more susceptible to eye infections. Diseases like diabetes can weaken overall eye health, and common ailments like the flu can leave your body unable to fend off bacteria that gets into the eye. Allergies can also cause or worsen eye infections. The cure for eye infections may include treatment of underlying conditions.

Treatment for eye infections

Antibiotics remain the most common treatment for eye infections. Antibiotics may be administered as eye drops if necessary, and often are accompanied by artificial tears to help keep the eye healthy. When eye infections are caused by viruses, antibiotics are less effective and typically only prescribed if a secondary bacterial infection has developed or is likely. Viral infections may be left to clear up on their own. More serious eye infections may require advanced treatments such as eye surgery.

Tips for avoiding eye infections

If you want to lower your risk of eye infections, consider the following easy tips.

When to go to a doctor

You should call your eye doctor and schedule an appointment if you notice any severe or persistent symptoms such as redness, pain, swelling, blurry sight or any noticeable changes in vision. The sooner treatment is started, the better the prognosis and the lower the chances of permanent damage. If you are ever unsure about whether an appointment is necessary, call your eye doctor and ask.