Shingles are triggered by the varicella-zoster virus. While this name might not ring any bells, this is the same virus that causes chickenpox.
Once you've had the childhood disease, the virus lies inactive in your nerve tissue near your spinal cord and brain. Years later, the culprit can reappear as shingles.
As medicine works best when taken within the first three days of your symptoms, being able to identify the early signs, including an "intense" symptom, could help.
According to the Mayo Clinic, one of the "first" symptoms of shingles is pain. Some people can experience a really "intense" pain, making the condition tricky.
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