When you think about infections you should guard against as an adult, you probably give chickenpox little thought. But did you know that if you had chickenpox as a child, the infection can stage a painful reappearance later in life in the form of herpes zoster—better known as shingles?

Shingles is caused by the varicella zoster virus—the same virus that gave you chickenpox when you were a child (more than 90 percent of American adults have had chickenpox) and has remained dormant in your body since you recovered. Your risk of shingles increases with age: As you get older, the virus can reactivate and migrate along the path of a nerve to the surface of the skin. This can cause severe burning or shooting pain, tingling and itching that's typically concentrated on one side of your body, usually on your chest or back, but sometimes on your face.

Within a day or two, a rash of blisters may form in a band or strip pattern on your skin and persist for up to 14 days. You may also suffer from fever, headaches and a feeling of general sickness. The rash can affect your sight and hearing if it appears on your face. And in some people the pain from shingles can linger for months or even years after the rash has healed, a complication known as postherpetic neuralgia.

The immune system link

Shingles is thought to be caused by a weakened immune system owing to aging or illnesses such as chronic lung or kidney disease and cancer. People with autoimmune diseases are at increased risk as well: Several studies suggest that immune-suppressing drugs used to treat diseases such as rheumatoid arthritis and inflammatory bowel syndrome may increase susceptibility.

An effective but underused vaccine

Despite shingles' harsh symptoms and the increasing risk with age, few older adults opt for getting the herpes zoster vaccine (Zostavax), which may prevent shingles (or a recurrence of shingles if you've already had an attack) and has been available since 2006. The Centers for Disease Control and Prevention (CDC) recommends that healthy adults ages 60 and up get the vaccine. Yet in 2010, only 14.4 percent of such Americans followed that advice, according to the CDC, even though up to a million cases of shingles are reported each year in the United States.

Zostavax, which contains a live strain of the varicella zoster virus, is approved by the Food and Drug Administration for adults ages 50 and older. Administered as a single shot, the vaccine is safe and well tolerated. It's covered by Medicare Part D and most insurance plans.

In people ages 60 and older, the vaccine's success rate was 51 percent for preventing shingles and 67 percent for preventing postherpetic neuralgia. Another study, published in the journal Clinical Infectious Diseases in April 2012, showed that the younger the patient, the more effective the vaccine; it was nearly 70 percent effective for adults ages 50 to 59. (The vaccine hasn't been tested in people under 50.)

Zostavax causes minimal side effects, if any, according to a recent study published in the Journal of Internal Medicine. The study found a slightly increased risk of allergic reactions within a week of receiving the vaccine, and some participants reported headaches. The allergic reactions weren't severe—typically temporary inflammation, swelling, itching and/or pain around the injection site.

Source: Prepared by the Editors of The Johns Hopkins Medical Letter: Health After 50

Publication Review By: the Editorial Staff at Healthcommunities.com

Published: 16 Jul 2013

Last Modified: 06 Oct 2015