The pain caused by herpes zoster is due to a disease caused by reactivation of the chickenpox virus in childhood. Having spent the disease, the virus remains dormant and reactive and sometimes certain areas like the face, neck, back, hands .... When it arises again, the herpes that affects the peripheral nerves appears and skin, causing pain, swelling and redness of the skin, where small vesicles or painful blisters grouped in the territory of a nerve are generated. In this phase of the outbreak lesions they are highly contagious, then the vesicles dry and scabs that can sometimes leave scars form. The main consequence is pain following herpes disease (post-herpetic neuralgia), and you can still have residual pain for months or years.