What is Shingles (Herpes Zoster)?
Shingles is caused by the varicella zoster virus, the same virus that causes chickenpox. After a person recovers from chickenpox, the virus stays in the body in a dormant (inactive) state. For reasons that are not fully known, the virus can reactivate years later, causing shingles. Herpes zoster is not caused by the same virus that causes genital herpes, a sexually transmitted disease.
Shingles usually starts as a painful rash on one side of the face or body. The rash forms blisters that typically scab over in 7 to 10 days and clears up within two to four weeks. Before the rash develops, there is often pain, itching, or tingling in the area where the rash will develop. This may happen anywhere from one to five days before the rash appears.
Most commonly, the rash occurs in a single stripe around either the left or the right side of the body. In other cases, the rash occurs on one side of the face. Rarely, usually among people with weakened immune systems, the rash may be more widespread and look similar to a chickenpox rash.
Other symptoms of shingles can include fever, headache, chills, and upset stomach.
The most common complication of shingles is post-herpetic neuralgia, or PHN. People with PHN have severe pain in the areas where they had the shingles rash, even after the rash clears up. The pain from PHN may be severe and debilitating, but it usually resolves in a few weeks or months in most patients. However, PHN can persists for many years in some persons.
PHN occurs rarely among people under 40 years old but can occur in up to half (and possibly more) of untreated people who are 60 years or older.
Shingles may lead to other serious complications involving the eye causing vision loss. Very rarely, shingles can also lead to pneumonia, hearing problems, brain inflammation (encephalitis), or death.
Who gets Shingles (Herpes Zoster)?
Nearly one out of three people in the United States will develop shingles in their lifetime. There are an estimated one million cases each year in this country. Anyone who has recovered from chickenpox may develop shingles; even children can get shingles. However, the risk of shingles increases as a person gets older.
About half of all shingles cases occur among men and women 60 years or older.
People with weakened immune systems have an increased risk of developing shingles. For example, people with certain cancers, including leukemia and lymphoma, and human immunodeficiency virus (HIV), and people who have undergone a bone marrow or organ transplantation, or who take immunosuppressive drugs.
People who develop shingles typically have only one episode in their lifetime. In rare cases, however, a person can have a second or even a third episode.