The Facts about Shingles

What is shingles?
Shingles is a localized infection due to the same virus that causes chickenpox. It occurs only in people who have had chickenpox in the past and represents a reactivation of the dormant virus. Why the virus reactivates in some individuals and not in others is unknown. Shingles can appear many years after a person has had chickenpox.

Who gets shingles?
Anyone who has had chickenpox in the past can get shingles. The disease is primarily seen in persons with weakened immune systems, such as the elderly and those with certain underlying medical conditions. It is estimated that 10-20% of the entire population and up to 50% of those persons who live beyond 80 years will have at least one episode of shingles.

How is shingles spread?
A person must have already had chickenpox in the past to develop shingles. Contact with a person with shingles does not cause another person's dormant virus to reactivate. However, the virus from a patient with shingles may cause chickenpox in someone who has not had chickenpox.

What are the symptoms of shingles?
The first symptom is often a tingling feeling on the skin, itchiness or a stabbing pain. After several days, a rash appears as a band or patch of raised dots on the side of the trunk or face. It then develops into small, fluid-filled blisters that dry out and crust over within a few days. When the rash is at its peak, symptoms can range from mild itching to severe pain. The rash and pain usually disappear within three to five weeks.

When and for how long is a person able to spread shingles?
The virus is present at the site of the rash and is contagious for a week after the appearance of lesions (blisters) or until vesicles become dry and crusted.

Does past infection make a person immune?
Yes. Most people who have shingles have only one episode of the disease in their lifetime although some may have recurrent episodes. Those with impaired immune systems (e.g., people with AIDS, cancer or leukemia) may suffer repeated attacks.

What is the treatment for shingles?
Most cases of shingles resolve on their own without specific treatment. Physicians can prescribe anti-viral medications for severe cases in individuals with a weakened immune system.

In 1999, the Food and Drug Administration approved a new method of treating the pain of postherpetic neuralgia. The product is an adhesive patch containing lidocaine, a commonly used local anesthetic. The patch allows lidocaine to be released into the top layers of the skin, reducing pain from the damaged nerves. Because it delivers the drug via the skin, it does not produce any significant levels of the drug in the blood and, therefore, does not cause serious systemic side effects if used appropriately.

Studies have also shown that some anticonvulsant drugs used to treat epilepsy, such as carbamazepine, are sometimes effective in relieving the pain of postherpetic neuralgia. Antidepressants can help also. In addition to their effects on mood, the antidepressants appear to relieve pain. Some doctors report that patients occasionally benefit from alternative treatments for pain, such as acupuncture and electrical stimulation of nerve endings.

It is important to realize that individuals with postherpetic neuralgia no longer have shingles: their infection is over. Instead, they are suffering from damage to the nervous system. Scientists believe that the virus attack has led to scarring or other lesions affecting the cells in sensory ganglia and associated nerves. Even in such severe cases, however, the paralysis, headaches, and pain generally subside, although it may take time.

What can be done to prevent the spread of shingles?
Chickenpox must be prevented in order to prevent shingles. A vaccine for chickenpox has been developed and may reduce the risk of developing shingles later in life.

This article is based on information provided by the Wisconsin Department of Health and Family Services and the National Institute of Neurological Disorders and Stroke.

Each year, Medical College of Wisconsin physicians care for more than 180,000 patients, representing nearly 500,000 patient visits. Medical College physicians practice at Children's Hospital of Wisconsin, Froedtert Memorial Lutheran Hospital, the Milwaukee VA Medical Center, and many other hospitals and clinics in Milwaukee and southeastern Wisconsin.