Immune system and shingles

The immune system protects the body against infection and disease. Some conditions and medications can weaken the immune system and set off reactivation of the virus that causes shingles. A weak immune system cannot effectively fight developing infections and illnesses.

Factors that may weaken the immune system, reactivate the chickenpox virus, and cause shingles include:

• Being age 50 or older.
• Recent surgery.
• Drugs or certain medications that suppress the immune system (immunosuppressive drugs).
• Radiation therapy.
• Serious illness or disease, such as cancer or AIDS.
• Poor nutrition.
• Stress.
• Chronic diseases that suppress the immune system, such as diabetes, lupus, or HIV.
• Injury.
• Organ transplant.