Shingles is a common dermatological disease primarily caused by the varicella-zoster virus. Shingles has an incubation period, but the duration is uncertain, generally ranging from 3 to 20 days. The reason the incubation period for shingles is variable is that after being infected with the varicella-zoster virus, it accumulates in the nerves of the spinal cord and does not exhibit any symptoms physiologically. The virus only begins to proliferate rapidly and triggers the disease when the body's resistance decreases, or in the event of an infection, a cold, or fatigue.