You can only get shingles if you already had chickenpox and the dormant virus from the chickenpox infection becomes reactivated. Since only 20% of people who have had chickenpox develop shingles, researchers are still trying to determine what makes some people more likely to develop shingles than others.

Some of the factors that make people more likely to develop shingles include:

If you have a weakened immune system, you are more likely to develop shingles. Conditions that increase your risk include:

Certain procedures and medicines may increase your risk, such as:

People over age 60 are more likely to develop shingles than younger people.

Caucasian people are more likely than African Americans to develop shingles.