What is shingles (Herpes Zoster)?

What is shingles (Herpes Zoster)?

Shingles, also known as herpes zoster, is a viral infection caused by the varicella-zoster virus. This is the same virus that causes chickenpox. Anyone who has had chickenpox may develop shingles later in life as the virus remains in your nervous system long after you have recovered. 

The virus can be reactivated at a later date, causing shingles. It’s not known exactly what causes this reactivation, but it may be linked to having a lowered immunity (your body’s ability to protect you from infection and disease). Common causes of changes to your immune system are:

  • old age
  • physical and emotional stress
  • taking medication that affects your immune system, such as chemotherapy medication
  • recently having had an organ or bone marrow transplant
  • having a condition that affects your immune system, such as HIV or AIDS
Although shingles can occur at any age, it is most common in people over 70. One in four adults are estimated to experience shingles at some point in their lives, and it is possible to get shingles more than once. Although the virus belongs to the herpes family, it is not the same as the viruses that cause genital herpes or cold sores.

Last reviewed: 16-04-2020 by Dr Simran Deo