Ans. A. Herpes zoster
Shingles, also known as herpes zoster, is a viral disease characterized by a painful skin rash with blisters in a localized area.
Shingles are due to a reactivation of varicella-zoster virus (VZV) within a person’s body.
The disease chickenpox is caused by the initial infection with VZV.
Once chickenpox has resolved, the virus may remain inactive in nerve cells.
When it reactivates, it travels from the nerve body to the endings in the skin, producing blisters. Risk factors for reactivation include old age, poor immune function.