Who gets shingles?
A person must have had chickenpox to get shingles. Some people who have had chickenpox have a higher risk of getting shingles. These people:
- Are 50 years of age or older.
- Have an illness or injury.
- Are under great stress.
- Have a weakened immune system.
Some illnesses and medical treatments can weaken a person's immune system and increase the risk. These include:
- Some cancer treatments, such as chemotherapy or radiation.
- Medicine taken to prevent rejection of a transplanted organ.
- Cortisone when taken for a long time.
What causes shingles?
The virus that causes chickenpox also causes shingles. After a person gets rid of the chickenpox, the virus stays in the body. The virus travels to the nerves where it sleeps. Shingles appears when the virus wakes up. It is not clear what reactivates or "wakes up" the virus. A short-term weakness in immunity may cause this.
Shingles is much less contagious than chickenpox. But a person with shingles can still spread the virus. Anyone who has not had chickenpox can get this virus.
If the virus spreads to someone who has not had it, the person will get chickenpox — not shingles. Newborns and those with a weak immune system have the highest risk of getting the virus from someone who has shingles.
This virus spreads when the person has uncovered, open blisters and someone touches the blisters. Once the blisters form scabs, the person is no longer contagious.
Learn more about shingles: