Herpes zoster is a viral skin disease that is most prevalent in the spring and is caused by the varicella-zoster virus infection, which is latent in the body and causes clusters of herpes in bands along the innervated areas of the skin, accompanied by neuralgia. The elderly and people with chronic wasting diseases are susceptible to herpes zoster, and the disease is more severe once contracted. The folklore of this disease is known as “string waist dragon” and in the literature it is called “tangled waist fire dan”, because herpes zoster that affects the chest and waist area accounts for more than 60% of the incidence of this disease. In fact, the disease can also invade the head, face, ears and upper and lower limbs. As the virus is nerve-friendly, it always develops along the nerves in a band, hence the name “herpes zoster”. In Chinese medicine, herpes zoster is thought to be caused by a strong fire in the liver and gallbladder and a long period of spleen and dampness, and is caused by external poison. Modern medicine has learned that the virus is invaded by respiratory infection and latent in the nerve cells of the posterior root ganglion of the spinal nerve or other sites of disease. The virus may not usually develop, but the elderly and people who have been ill for a long time have a reduced resistance to the disease, and when they encounter physical exertion, colds and other triggers, they are prone to develop the disease. Pathogenesis The primary infection, chickenpox, can occur in people (mostly children) who are not immune or have low immunity after virus infection. When the immunity of the body decreases (e.g., trauma, cold, cancer, immune system diseases, etc.), the latent virus multiplies and causes inflammation and necrosis of the ganglion, resulting in pain in the patient. The virus travels down the nerve pathway to the area innervated by that nerve causing segmental herpes. The virus can also infect motor neurons, causing muscle weakness and motor paralysis, but this is rare. At the beginning of the disease, the main symptoms are generalized fatigue and weakness, loss of appetite, mild fever, and soon a burning, throbbing pain at the site of the attack. If it occurs in the chest or lower back, it is often misdiagnosed as heart disease or acute abdomen, etc. When you get herpes zoster, 1 to 3 days later, the skin at the onset site appears as green pea-sized, very tense papules and blisters, which are distributed along the nerves and arranged in clusters in a striped pattern. If it occurs on the chest or waist, it is more likely to occur from the side of the spine diagonally downward, and rarely symmetrically. The folklore that a circle of herpes around the waist is life-threatening is not reliable. In mild cases, each cluster can be spaced with normal skin, but in severe cases, they can be fused into a large band-like distribution, and after a few days, they can change from clear blisters to cloudy pustules, and some can break down to form vesicles. In the elderly, the disease is often characterized by large, bloody blisters and even necrosis. In mild cases, the blisters dry up naturally in about three weeks and crust over, leaving no scar after shedding; in severe cases, the course of the disease can extend to more than a month. Elderly patients often experience severe pain that affects sleep, and if treatment is not timely, pain remains after the lesions have subsided and does not completely subside for months. If herpes zoster appears on the head and face, be alert for headaches and facial paralysis due to invasion of the head and facial nerves. If the cornea of the eye is invaded, it can even lead to blindness. The condition can be more serious in older, weaker people and those with chronic diseases such as tumors. It is important to note that there is also an incomplete form of herpes zoster, where the blisters do not appear or appear rarely, except for severe pain at the onset of the disease, which can be easily misdiagnosed and should be taken seriously to avoid delaying treatment and finding serious consequences. Patients with herpes zoster should ask their doctor to confirm the diagnosis and actively treat them when they are not experiencing pain at the site.