Diagnosis 1. Clusters and clusters of blisters appear on the lesioned skin, distributed in a band along one side of the peripheral nerve. 2, There is obvious neuralgia with local lymph node enlargement. 3, the intermediate skin is normal. Differential diagnosis 1, the disease sometimes needs to be distinguished from herpes simplex, the latter occurs at the junction of skin and mucous membrane, the distribution is not necessarily regular, the blisters are small and easy to break, pain is not present, most often seen in the course of fever (especially high fever) disease, often easy to recur. Occasionally, it is confused with contact dermatitis, but the latter has a history of contact, the rash is not related to the distribution of nerves, self-conscious burning, severe itching, and no neuralgia. 3. In the prodromal phase of herpes zoster and herpes zoster without rash, neuralgia is easily misdiagnosed as intercostal neuralgia, pleurisy, and acute abdominal conditions such as acute appendicitis, which require attention. 4. Herpes simplex usually has a history of multiple recurrences at the same site, whereas this phenomenon does not occur in patients with herpes zoster without significant immunodeficiency. Isolation of the virus from blister fluid or detection of VZV, HSV antigen or DNA is the only reliable method for differential diagnosis.