Eye Disorders: Shingles, also known as Vericella Zoster Virus, or Herpes Zoster
Shingles is rash that breaks out on the skin caused by the virus that causes chicken pox. The virus is called Varicella Zoster Virus (VZV), or Herpes Zoster. It is a member of the herpes class of viruses, which include herpes simplex type 1 and 2, cytomegalovirus, and Epstein Barr virus. Herpes simplex type 1 is a common cause of eye disease. If Shingles occurs around the eye, the eye itself may become infected.
What causes Shingles?
When people are exposed to chicken pox, the VZV virus takes up residence deep in the peripheral nervous system for the rest of your life. This behavior is common to all Herpes viruses. During one's life, often for unclear reasons, VZV can migrate along the nerve to the skin or mucous membranes and cause active disease. Certain systemic diseases, exposure to sunlight, or immunosupressive medications make this more likely to occur.
What are the symptoms of Shingles?
When the virus begins to reactivate, the first symptoms are usually several days of tingling or pain along the nerve that is involved. Most commonly VZV involves nerves to the trunk. The second most common location is the sensory nerve to the forehead (called the trigeminal nerve). After several hours to days of pain, blisters that look like chicken pox begin to appear on red skin usually on the forehead and behind the hair line on one side of the face. The skin outbreak can be quite severe and deep, resulting in scarring. Sometimes the outbreak can occur in the eye itself. In that case, blurry vision, red eyes, sensitivity to light, and eye pain may develop. Glaucoma (high eye pressure) is commonly seen with intraocular involvement.
How are Shingles treated? Can I loose my vision?
If the condition is noted early enough (usually within several days of onset of pain or rash), antiviral medication by mouth is prescribed. If the eye becomes involved, topical steroids or antibiotic drops may be prescribed depending on the specific situation. The antiviral medication by mouth will also treat any active eye infection. If glaucoma is present, topical drops to lower eye pressure may be prescribed. In the majority of patients, the ocular involvement will resolve uneventfully.
Unfortunately, in a small number of patients, ocular inflammation can persist for quite a long time, even years. Chronic treatment with steroid eye drops is effective, but may cause cataracts or high eye pressure that may require surgical or medical therapy. Rarely, chronic corneal inflammation can lead to scarring and decreased vision, in which case a corneal transplant may be an option. Permanent vision loss from ocular VZV infection is quite rare, however.
Am I contagious?
The liquid in the blisters contain active virus. If someone who has not had chicken pox comes into contact with the secretions, they could contract chicken pox (not shingles). Consider staying away from children and people with compromised immune systems if they haven't had chicken pox.
More information on this condition can be found at the National Eye Institute's website, under the corneal section.