Herpes Zoster Infections

What is Herpes Zoster (HZV)?

Herpes zoster (HZV), also known as shingles or zoster, is a viral infection caused by the same virus that causes chicken pox. Anyone who’s had chicken pox can develop herpes zoster. The virus remains dormant or inactive in certain nerve root cells of the body and only when it reactivates does zoster occur. About 20 percent of those people who have had chicken pox will get zoster at some time during their lives. Fortunately, most people will get zoster only once.

It is not clear what prompts the virus to reactivate or “awaken” in healthy people. A temporary weakness in immunity (the body’s ability to fight infection) may allow the virus to multiply and move along nerve fibers toward the skin. Although children can get zoster, it is more common in people over the age 50. Illness, trauma and stress may also trigger a zoster attack.

What are the symptoms of Zoster?

The first symptom of zoster is burning pain, tingling or extreme sensitivity in one area of the skin, usually limited to one side of the body. This may be present for one to three days before a red rash appears at that site. There may also be fever or headache. The rash soon turns into groups of blisters that look a lot like chicken pox. The blisters generally last for two to three weeks. The blisters start out clear but then pus or dark blood collects in the blisters before they crust over (scab) and begin to disappear. Pain may often occur over the area of the rash.

Where would I see zoster on my body?

Zoster is most common on the trunk and buttocks. But it can also appear on the face, arms or legs if nerves in these areas are involved.

What are the complications of zoster?

“Post-herpetic neuralgia” is constant pain or periods of pain that can continue after the skin has healed. It can last for months or even years and is more common in older people. The use of medication in the early stages of the zoster may help prevent this complication. A bacterial infection of the blisters can occur and can delay healing. Antibiotic treatment may be given if this occurs.

How is zoster diagnosed?

The diagnosis is based on the way the blisters look and a history of pain before the rash on one side of the body. The dermatologist may scrape skin cells from a blister onto a glass slide for examination. The glass slide is then examined under a microscope for signs of zoster.

Is zoster contagious?

The virus that causes zoster can only be passed on to others who have not had chicken pox and then they will develop chicken pox, not zoster. Zoster is much less contagious than chicken pox. Persons with zoster can only transmit the virus if blisters are not crusted over. Newborns or those with decreased immunity are at the highest risk for contracting chicken pox from someone who has zoster. Patients with zoster rarely require hospitalization.

Is there much scarring?

Scarring usually occurs only after more severe infections, such as in those with weakened immune systems, elderly persons or those whose blisters become infected.

What about treatment?

Zoster usually clears on its own in a few weeks and seldom recurs. Pain relievers and cool compresses are helpful in drying the blisters. If diagnosed early, oral antiviral drugs can be prescribed to decrease both viral shedding and the duration of skin lesions. They are routinely prescribed for severe cases of zoster – with eye involvement, for example – or for those with decreased immunity.