It causes a painful rash that may appear as a strip of of vesiculobullous lesions that does not cross midline(unilateral). Pain can persist even after the rash is gone (This is called post Herpetic neuralgia). It typically presents with pain described as burning or stabbing, followed by vasicular rash in the affected dermatome, Presence of symptoms/lesions depends upon the nerve which is affected. The diagnosis is usually clinically made such as dermatomal pain and eruption of grouped vesicles in the same dermatome. Confirmation can be done using polymerase chain reaction(PCR) method. Treatment is primarily to reduce neurologic pain & viral replication using antiviral medication such as acyclovir/valcilovir.

Antiviral therapy usually at the start of lesions (within 48 hours) effectively reduce the severity of postherpetic neuralgia. Early start of antiviral therapy is particularly important in Herpes Zoster Opthalimicus (HZO) in the immunocompromised/old-age.
Herpes zoster caused by reactivation of varicella-zoster virus (VZV) that was acquired during primary vericella infection( Chickenpox or due to vaccination), is characterized by dermatomal pain (pain limited to one side) and papular rash. The pain typically precedes the rash by several days and can persists for weeks to months after the rash resolves.

How to identify Herpes zoster Diagnostic features :

• Localised pain a dermatome unilateral burning or stabbing pain.
• Abnormal sensation.
• Rash papular to grouped vesicles.
• Involvement of eye corneal ulceration.
• Patients can have fever, headache, malaise and fatigue.

Who are more prone to develop Herpes zoster :

• Person above 50 years of age.
• HIV Positive person.
• Chronic steroid steroid abuse.
• Person on chemotherapy.