Shingles is the name commonly used for herpes zoster, an infection that shows up as a painful skin rash with blisters, usually on part of one side of the body (left or right), often in a strip. Shingles is caused by the varicella zoster virus.
People get shingles when the virus that causes chicken pox, varicella zoster, is reactivated in their body. The varicella zoster virus doesn’t leave the body, even after a person has recovered from chicken pox. It can flare up again, causing shingles, often many years after a person has had chicken pox. The virus tends to reactivate when a person’s immune system is weakened because of another health problem.
People with shingles often experience pain, tingling or itching and then a painful rash. The rash can occur anywhere on the body, although it is usually in one strip on the right or left side of the body. The rash consists of groups of small, fluid-filled blisters that dry, scab over, and heal (like chickenpox) in a few weeks. Healing is usually complete, but some people may be left with scars.
Some people experience pain around the rash site for a month or more—pain that is severe enough to interfere with daily activities.
Scratching the rash can also cause a secondary infection if harmful bacteria get into the sores.
Shingles on the face can involve the eyes, which is serious because it can cause scarring and blindness.
The occurrence and severity of shingles and its complications increase with age.
A doctor can diagnose shingles by examining the rash and, if necessary, taking a sample of the fluid from one of the blisters.
Although any person who has had chickenpox can get shingles, most people who do so are older than 50 or have a weakened immune system. For example, a person might be susceptible if they have cancer, take medicines that weaken their immune system, or have HIV or AIDS, even if they are younger than 50.
The best protection from shingles is vaccination. People can still get shingles after receiving the varicella vaccine but they are 4 to 12 times less likely to do so than if they haven’t been immunized. The vaccine is recommended for most people 60 and older.
Some people should not receive the vaccine; for example, those with certain allergies or who are taking certain medications. A health professional can advise who should not be vaccinated due to contraindications to the vaccine.
People between 50 and 59 years can request the vaccine from their health professional.
Shingles is often treated with antiviral medication to reduce the severity and duration of the symptoms. This medication works best if taken in the first three days after the rash appears. A doctor might also prescribe additional medication for pain and swelling.