Herpes keratitis is a viral infection of the eye caused by the herpes simplex virus (HSV). There are two major types of the virus:
- Type I is the most common and primarily infects the face, causing the familiar "cold sore" or "fever blister."
- Type II is the sexually transmitted form of herpes, infecting the genitals.
While both Type I and Type II herpes can spread to the eye and cause infection, Type I is by far the most frequent cause of eye infections. Infection can be transferred to the eye by touching an active lesion and then your eye. It is rare to transfer Type II to the eye.
What causes herpes keratitis?
Type I herpes is very contagious and is commonly transmitted by skin contact with someone who has the virus. Almost everyone — about 90 percent of the population — is exposed to Type I herpes, usually during childhood.
After the original infection, the virus lies in a dormant state, living in nerve cells of the skin or eye. Reactivation can be triggered in a number of ways, including:
Once herpes simplex is present in the eye, it typically infects the eyelids, conjunctiva and cornea. It may also infect the inside of the eye; however, this is much less common.
The symptoms of herpes keratitis may include:
- blurred vision
- sensitivity to light
If the infection is superficial, involving only the cornea’s outer layer (called the epithelium), it will usually heal without scarring. However, it if involves the deeper layers of cornea (which can happen after time), the infection may lead to scarring of the cornea, loss of vision and sometimes even blindness.
Left untreated, herpes keratitis can severely damage your eye.
Herpes keratitis treatment
Treatment of herpes keratitis depends on its severity. Mild infection is typically treated with topical and sometimes oral antiviral medication. Your ophthalmologist may gently scrape the affected area of the cornea to remove the diseased cells. In case of severe scarring and vision loss, a corneal transplant may be required.
It is very important to consult an ophthalmologist before beginning any treatment, because some medications or eyedrops may actually make the infection worse.
There is no complete cure for herpes; once the virus is in the body, you cannot get rid of it. However, if you develop herpes keratitis, there are some things you can do to help prevent recurring outbreaks:
- If you have an active cold sore or blister, avoid touching your eyes.
- Steroids can increase the herpes virus in the body. You should not use steroid eye drops unless you are taking an anti-viral medicine as well.
- Stop wearing contact lenses if you keep getting infections.
- See an ophthalmologist immediately if symptoms of ocular herpes return.