Ocular herpes is a common viral infection affecting the eyes, caused by the type 1 herpes simplex virus. This recurrent condition typically causes inflammation and scarring to the cornea and can be transmitted when in close contact with someone whose virus is active.
Caused by the type 1 herpes simplex virus, eye herpes (ocular herpes) is a common, recurrent viral infection affecting the eyes. This type of herpes virus can cause inflammation and scarring of the cornea that sometimes is referred to as a cold sore on the eye. Herpes of the eye can be transmitted through close contact with an infected person whose virus is active.
The National Eye Institute (NEI) says an estimated 400,000 Americans have experienced some form of ocular herpes, with close to 50,000 new and recurring cases occurring each year.
Forms Of Eye Herpes
Ranging from a simple infection to a condition that can possibly cause blindness, there are several forms of eye herpes:
Herpes keratitis is the most common form of eye herpes and is a viral corneal infection. Ocular herpes in this form generally affects only the top layer, or the epithelium, of the cornea, and usually heals without scarring.
Stromal keratitis occurs when the infection goes deeper into the layers of the cornea. This can lead to scarring, loss of vision and, occasionally, blindness. Stromal keratitis is thought to be caused by a late immune response to the original infection. According to NEI, about 25 percent of new and recurring cases of herpes eye infections result in stromal keratitis.
Iridocyclitis is a serious form of eye herpes where the iris and surrounding tissues inside the eye become inflamed, causing severe sensitivity to light, blurred vision, pain and red eyes. Iridocyclitis is a type of uveitis that affects the more frontal portions of the inside of the eye. When this infection occurs in the retina or the inside lining of the back of the eye, it is known as herpes retinitis.
Eye Herpes Symptoms And Signs
Various signs and symptoms are associated with an ocular herpes outbreak. You may experience inflammation of the cornea, which can cause an irritation or sudden and severe ocular pain. Also, the cornea can become cloudy, leading to blurry vision.
Other characteristics of eye herpes include:
Recurrent eye infections
Foreign body sensation
Watery eye discharge
Due to these numerous symptoms, your eye doctor may overlook an initial diagnosis of ocular herpes in its very early stages.
What Causes Eye Herpes?
Eye herpes is transmitted through contact with another person who is having an outbreak, or through self contact and contamination during an active herpes infection (such as a cold sore of the lip).
The herpes simplex virus enters the body through the nose or mouth and travels into the nerves, where it may be inactive. The virus can remain dormant for years and may never wake up.
The exact cause of an outbreak is unknown, but stress-related factors such as fever, sunburn, major dental or surgical procedures and trauma are often associated with incidents.
Once the initial outbreak occurs, the NEI says untreated eye herpes has about a 40-50 percent chance of returning. There is no specific time frame for ocular herpes to reappear; it could be several weeks or even several years following the original occurrence. Although symptoms usually present themselves in only one eye, the virus possibly could affect the other eye as well.
Eye Herpes Treatment
Treatment for eye herpes depends on where the infection is located in the eye — in the corneal epithelium, corneal stroma, iris, retina, etc. Some ocular herpes treatments could aggravate the outbreak and therefore should be considered on a case-by-case basis.
If the corneal infection is only superficial, it can normally be alleviated by using antiviral eye drops or ointments, or oral antiviral pills.
Zirgan (Sirion Therapeutics) is an FDA-approved topical antiviral treatment for eye herpes. The treatment (ganciclovir ophthalmic gel, 0.15 percent) involves instilling eye drops five times daily until the related corneal ulcer heals. You should not wear contact lenses while undergoing treatment with Zirgan, which is marketed in Europe as Virgan.
Other treatments for herpes eye infections include Viroptic (trifluridine) eye drops and Vira-A (vidarabine) ointment.