Herpes zoster ophthalmicus (HZO), or shingles of the eye, may be associated with severe and long-lasting eye disease and pain. It can cause permanent loss of vision and reduced quality of life.

Shingles of the eye can occur in anyone who has had chickenpox. Most people in the United States age 40 years or older have had chickenpox, whether they know it or not. After a person has had chickenpox, the varicella-zoster virus stays in the body and lies dormant (asleep) in nerve cells. At some point later in life, the immune system weakens, allowing the virus to become active again and cause shingles, sometimes in the eye and in other parts of the body.

Shingles usually causes a painful rash with blisters located on one side of the body. About a million people per year in the United States develop shingles, 10 to 20 percent of whom will have HZO. The largest number of cases occurs in people in their 50s, and although the risk of shingles increases dramatically with age, approximately half of the cases occur in persons under age 60.

Chronic or recurrent activation of the shingles virus after an attack contributes to complications, including eye disease and, on rare occasions, stroke. Long-term, low-dose oral antiviral medication reduces recurrences of a related herpes simplex virus in the eye and elsewhere. NYU Langone’s Zoster Eye Disease Study (ZEDS) aims to find out whether valacyclovir, a drug approved for prolonged treatment of genital herpes simplex infections, is also effective in reducing complications of HZO.