Herpes zoster

Herpes zoster is an acute infectious skin disease caused by the varicella-zoster virus. Children without immunity to this virus develop chickenpox after infection. Some patients become virus carriers after infection without developing symptoms. Because the virus is neurotropic, it can remain latent for a long time in the neurons of the dorsal root ganglia of the spinal cord after infection. When resistance is low, or due to fatigue, infection, or a cold, the virus can reactivate and multiply, migrating along nerve fibers to the skin, causing intense inflammation in the affected nerves and skin. The rash generally has the characteristics of unilaterality and dermatomal distribution, consisting of clustered vesicles, and is accompanied by pain; the older the patient, the more severe the neuralgia. This disease predominantly occurs in adults and is more common in spring and autumn. The incidence increases significantly with age.