Shingles (Herpes Zoster)

What Is It?

Shingles, also known as herpes zoster or just zoster, is a reactivation of a virus in nerve cells that results in a distinctive skin rash.

The virus that causes shingles, varicella-zoster virus, is the same virus that causes chickenpox. It is a member of the herpes virus family. Once you have had chickenpox, varicella-zoster virus lies dormant in your body's nerve tissues and never really goes away. Shingles occurs when the virus is reactivated.

Physicians are unsure how or why the varicella-zoster virus reactivates, but the prevailing theory is that your protective immune response wanes over the years after childhood chickenpox. When the virus does reactivate, it travels through nerves, often causing a burning or tingling sensation in the affected areas. Two or three days later, when the virus reaches the skin, blisters appear grouped in the distribution of the affected nerve. The skin may be very sensitive, and you may feel a lot of pain.

If you have had chickenpox, you are at risk of developing shingles. Shingles, however, most often appears in people older than 50 and in people with weakened immune systems. If you are undergoing cancer treatment, for example, you are more likely to get shingles. People with HIV commonly get shingles, which is often one of the first signs that the immune system is in trouble.

Your chances of getting shingles increase as you get older, although the disease can occur at any age. When shingles appears in children, which is uncommon, it usually is very mild. Up to 20 percent of the U.S. population develops the disease at some point.

Potential complications of shingles include:

• Post-herpetic neuralgia — About 10 percent of adults who get shingles experience long-term pain in the area of skin where blisters occurred, even after the rash has completely healed. This condition, called post-herpetic neuralgia, may last for months or, very rarely, years. This severe pain is most common in older patients and often is accompanied by extreme sensitivity to heat and cold in the affected area of skin.
• Herpes zoster ophthalmicus — This occurs when shingles involves the eye. Herpes zoster ophthalmicus can affect your vision, even causing blindness, and can be very painful.
• Otic zoster — Otic zoster, also called Ramsay Hunt syndrome or geniculate zoster, occurs when shingles affects the ears. Hearing loss may result.
• Bell's palsy — Shingles can cause Bell's palsy, in which a facial nerve is paralyzed.

Symptoms

Shingles typically begins with a burning sensation, a mild itching or tingling or a shooting pain in a specific area of skin. The affected area usually is located only on one side of the chest, abdomen or face or on a portion of an arm or leg. The affected skin may be extremely sensitive, so that even the touching or rubbing of clothing may be intolerable.