Why does shingles produce a painful rash along the path of a sensory nerve?

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skin rash caused by Lyme disease — skin disease Visible alterations in the texture of the skin, such as rashes and hives, can be indicative of serious disease. For example, one of the first signs of Lyme disease is a circular rash in a bull's-eye pattern on the skin.

Shingles, or herpes zoster, occurs when the varicella-zoster virus—the same virus responsible for chickenpox—reactivates after lying dormant in sensory neurons or sensory ganglia for years.12

The characteristic painful rash follows the path of a sensory nerve because, upon reactivation, the virus resumes replication and travels from the nerve-cell bodies along the length of the nerve until it reaches the skin. As the virus moves along this pathway, it triggers intense inflammation within the nerve and at the skin surface, resulting in a burning or tingling sensation and the development of a stripe-like rash of blisters that traces the specific distribution of the affected nerve segment.1