Varicella Zoster Virus (VZV) causes 2 infections. The first is chicken pox, which tends to affect children. After causing chicken pox, the virus remains in a specific nerve, where it can be reactivated later in life and cause the second infection (shingles). This reactivation typically occurs when the immune system is down. The shingles infection can occur in different parts of the body in different people, as it depends where the virus decided to lay dormant (asleep). In some people, this nerve affects one side of the upper face, including the eye. These individuals get a painful rash on one side of the forehead, the upper eyelid and down the nose, and can get an inflammatory/infectious reaction on the cornea (front surface) or inside the eye. This inflammatory reaction will cause the eye to get red, painful, and light-sensitive. Sometimes vision can get blurry, or it can feel like there is something stuck in the eye (foreign body sensation).
Treatment for ocular shingles includes an oral anti-viral medication as well as anti-viral eye drops. This infection may be prevented with a vaccine.