What is herpes zoster? 

Herpes zoster (shingles) is caused by the reactivation of the varicella-zoster virus, which is the same virus that causes chickenpox. After a person has had chickenpox, the virus may lie dormant in the sensory nerves. Sometimes the virus reactivates resulting in an outbreak of herpes zoster.

Herpes zoster occurs in more than 1 million individuals each year in the U.S. Approximately 30%, or one in every three people, will develop shingles. People who received the chickenpox vaccine also have a small risk of developing herpes zoster.

The incidence of herpes zoster in children is low, although children with depressed immune systems have a greater risk and may experience more severe symptoms. In addition, children who had chickenpox during the first year of life, or whose mothers had chickenpox very late in pregnancy, are also at risk. The risk of acquiring the disease is especially significant for people over age 50 due to a waning of immunity to the varicella-zoster virus.

What are the symptoms of herpes zoster?

The virus usually results in a painful rash or small blisters on a small section of one side of the body. On some occasions, even after the rash is gone, pain may continue for a prolonged period of time. This is called postherpetic neuralgia (PHN). 

Herpes zoster most often occurs on one side of the trunk or back. However, it may also appear on the face, arms, or legs. The following are the most common symptoms of herpes zoster, however, each person may experience symptoms differently. Symptoms may include:

• Pain, burning, tingling or numbness before the onset of the rash as well as following resolution
• Fluid-filled blisters which open and scab over
• Rash which usually resolves in two to four weeks
• Fever, chills, headache, nausea
• Postherpetic neuralgia (PHN) causing pain that is persistent after resolution of the rash and lasting for weeks, months or possibly more than a year

The symptoms of herpes zoster may resemble other skin conditions. Always consult your primary care provider for a diagnosis.

How is herpes zoster diagnosed?

Diagnosis can usually be made upon a medical history and physical examination. However, sometimes testing is indicated. Testing may include:

• Viral testing of skin scrapings of blisters
• Blood tests

What is the treatment for herpes zoster?

Immediate treatment with antiviral drugs may help lessen the duration and severity of some of the symptoms. These antiviral medications (acyclovir, famciclovir and valacyclovir) are more effective the sooner they are started. Medications like acetaminophen and ibuprofen may help alleviate some of the pain, but the disease has to run its course. Use of medication will be determined by your primary care provider based on factors including duration and severity of the symptoms.

How can I prevent herpes zoster?

The CDC recommends vaccination at age 50-60 for all individuals who have had chickenpox or the chickenpox vaccine. Zostavax® is a single dose live virus vaccine recommended starting at age 60. Shingrix® is a newer non-live vaccine given in two doses starting at age 50. Shingrix has been found to be more than 90% effective in preventing shingling and PHN. Zostavax is less effective; 50% effective in preventing shingles, 67% effective in preventing PHN.  

Learn more about shingles and the shingles vaccine at CHOP's Vaccine Education Center.