Herpes zoster is an acute herpetic skin disease that spreads like a band around the waist, so it is called “waist-wrapping dragon”. In Chinese medicine, there are many other names for this disease, such as “waist-wrapping fire-dan”, “snake-dan” and “snake-string sore”. Herpes zoster occurs in spring and autumn and is more common in adults. The onset of the disease is often preceded by localized skin sensitization or neuralgia, accompanied by mild fever, general malaise, loss of appetite and other prodromal symptoms, or sudden onset without prodromal symptoms. The affected area first develops flushed patches, followed by the appearance of numerous clusters of corn to green bean-sized papules, which rapidly turn into blisters, with transparent and clear blisters, shiny and tense walls, and a red halo around the blisters. The skin between the clusters of blisters is normal and the blisters dry up and crust over 10 days. After healing, temporary light red spots or hyperpigmentation are left without scars. The blisters can also break down to form vesicles or even necrosis or secondary septic infection. The total duration of the disease is about 2-3 weeks. In addition to the typical rash, neuralgia is another characteristic of the disease. The neuralgia is usually present 1 to 2 days before the appearance of the rash until the rash subsides. The pain varies in severity and is not necessarily related to the severity of the rash. Usually children with shingles have very mild or no pain, while older patients tend to have severe, even unbearable pain. Moreover, about 30% to 50% of middle-aged and elderly patients may have intractable neuralgia that lasts for months or longer after the damage subsides. Because of the rapid onset of herpes zoster, the pain is severe, and new rashes appear at the beginning of the disease, which is like a dragon and snake crawling, some patients feel afraid. And there is also a folklore saying that the entangled dragon will die if it wraps around the waist once, which is not based on science. The disease is caused by the herpes zoster virus and the lesions are often distributed unilaterally along one of the peripheral nerves, generally not exceeding the midline of the body surface, much less forming a circle. In addition to commonly occurring on the lower back and abdomen, they can also occur on the chest, extremities, neck, ears, nose, eyes, and mouth. In a few severe cases, herpes zoster meningoencephalitis and herpes zoster of the gastrointestinal or urinary tract may occur. Herpes zoster and chickenpox are caused by the same virus (varicella-zoster virus), but the clinical manifestations are different, why? We know that chickenpox is an infectious disease, so is shingles also contagious? On the surface, the two diseases are not related. The two are not related. Chickenpox occurs in children between the ages of 3 and 9, and there is no neuralgia; herpes zoster is seen in adults over the age of 40, and the pain is intense. The rash pattern and distribution characteristics of the two are also different. However, they are two successive pathogenic processes caused by the same virus that infects the body. Herpes zoster is not caused by the virus outside the body, but only by the recurrence of the virus latent in the body. The specific process is as follows: the virus first infected the body proliferates in the body, forming a viraemia that spreads throughout the body, leading to the occurrence of chickenpox. The virus can remain latent in the posterior root ganglion of the spinal cord or in the sensory ganglion of the cranial nerve until adulthood, when the latent virus is activated due to a decrease in immunity and stimulation by physical and chemical factors, causing inflammation and necrosis of the invaded ganglion, resulting in neuralgia. At the same time, the reactivated virus can proliferate along the nerve axon to the innervated skin cells, so that a series of band-like herpes appears in the skin area innervated by this ganglion, hence the name herpes zoster. There are several points to note here: ① Most people are infected with varicella zoster virus during childhood, but only some of them have clinical manifestations of chickenpox, and many others are asymptomatic or have very mild symptoms and are ignored; ② The body develops lasting immunity after the initial infection and rarely suffers from chickenpox again, but specific immunity cannot clear the latent virus in the ganglia, so it cannot prevent the occurrence of herpes zoster; ③ The occurrence of herpes zoster is due to a decrease in the body’s immunity, which is triggered by many factors, such as colds, overwork, certain infectious diseases, malignant tumors, AIDS, systemic lupus erythematosus, radiation therapy, burns, and the use of certain drugs (such as immunosuppressants and adrenocorticosteroids, antimony, arsenic, etc.). As can be seen, a person can have chickenpox or shingles successively during his or her lifetime, or only one of them can occur, or there can be no manifestation of the virus despite the infection. Theoretically, there is a virus in the blister fluid of a person with herpes zoster, and children who are not immune to this virus can be infected with chickenpox if they come in contact with the blister fluid, but the chance of this happening is relatively small. Adults are mostly immune, so they will not develop the disease even if they are exposed to it. Therefore, herpes zoster does not cause an epidemic in the population. Patients with shingles also do not require special isolation, but close contact with children should be avoided. Herpes zoster occurs in several specific areas (a) Herpes zoster in the area innervated by the ophthalmic branch of the trigeminal nerve unilateral frontal and scalp erythematous blisters, the periocular area can be significantly swollen, the conjunctiva is flushed and congested, blisters appear on the conjunctiva and even the cornea, ulcerative keratitis can occur, after healing the formation of corneal cloud opacities and affect vision, in severe cases, blindness. The pain is severe. (b) Ear herpes zoster is caused by viral invasion of the facial and auditory nerves and manifests as facial paralysis, tinnitus, deafness and hearing symptoms, with herpes in the external ear canal and tympanic membrane. (iii) Herpes zoster of the gastrointestinal and urinary tracts.