Just after winter, spring season, cold and temperature alternation, the ancients called “gas alternation”. Under normal circumstances, after the beginning of spring, the temperature gradually rebounded, increasingly warm, if a sudden “cold wave” attack, Chinese medicine is called “violent cold”, which exceeds the normal range of regulation of the human body, breaking the “unity of heaven and man ” (the balance of harmony and unity between man and nature). This special bad temperature (cold) is the evil, become a causative factor, leading to cold disease evidence, triggering the overall and local lesions, mostly cold disease evidence. First, the characteristics of the cold evil cause disease cold is a yin evil, mainly harming the body’s yang energy, so that it loses its function of warming and nourishing the organs, meridians, blood vessels, skin, muscles and other tissues. It causes cold symptoms or induces other diseases. The main clinical manifestations are: body temperature does not rise, fear of cold, skin bumps, chills, body surface and extremities syncope cold, lips and extremities now blue. Second, the common evidence: 1, the cold evil offending the brain: cold evil directly in the cranial blood vessels, stagnant blood stasis, poor circulation, sudden obstruction. Most commonly seen in stroke, cerebral infarction, manifested as headache, vomiting, cold extremities, dilated pupils, confusion, rescue is not timely, inappropriate, can be sudden death. 2, the cold offends the heart: cold directly to the central artery (or the original heart disease), so that blood stasis. Such as acute myocardial infarction, angina pectoris. Symptoms are chest pain, chest tightness, restlessness, hands and feet cold, pulse can not be felt, the serious “hair and death”. 3, cold offenses lung: external cold from the skin, mouth and nose, damage to the lungs, trachea, inducing and aggravating the original disease, such as chronic bronchitis, asthmatic bronchitis, or even cause phlegm and dampness obstruction of the lungs, trachea, severe pneumonia, respiratory failure and death. It is common in the elderly and children groups. Some early manifestations are only cold-like symptoms, which are neglected and lead to aggravation and irreversibility. 4, epidemic: cold evil caused by the “cold epidemic”. It is extremely contagious, epidemic, and extremely dangerous, such as the “SARS” initially found in the south in 2003. In the late winter and early spring of that year, when the weather was extremely cold, research showed that the pathogen was the coronavirus, which was closely related to the “cold”. Older people are weak, the internal organs are declining, and the power of cold is low; children’s childish bodies, the form of gas is not full, the internal organs are delicate. Therefore, the elderly and children are weak, the immune function is impaired, the resistance to disease is reduced, vulnerable to the “cold” evil attack, suffering from various cold disease evidence. Third, the prevention of the elderly, children’s cold disease evidence points: 1, strengthen the importance of the danger of cold disease and the significance of prevention and treatment. Establish a sense of prevention and maintain a high degree of vigilance. 2, scientific formulation of prevention programs (measures). According to the four seasons of climate change and the occurrence of special weather and the principle of “cold is warm”, from clothing, food, housing and transport, take measures to improve the body’s vitality (resistance to disease), prevent cold, avoid cold, keep warm, etc.. For example, it is advisable to eat foods rich in protein, vitamins and high heat and energy, such as: beef, lamb, pork, poultry and eggs, pungent and warm vegetables, ginger, garlic, onion, pepper, etc. It is advisable to control outdoor activities, not to travel far, and not to gather activities. The living environment needs to keep warm, but also to maintain clean and fresh air. Appropriate use of mugwort, vinegar, fumigation and other methods. The use of aromatic, pungent and warm drug decoction on the surface of the body can prevent and control frostbite by applying local rubbing or foot bath. 3, actively treat the original chronic diseases. Such as chronic bronchitis, asthmatic bronchitis, emphysema, pulmonary heart disease and other heart disease, stroke, diabetes, hypertension, etc., must adhere to treatment, not arbitrary interruption. 4, seize the cold disease evidence of the aura, prevention before it is too late. The aura of cold disease is manifested as: fear of cold, chills (war), pain, no sweat, body temperature does not rise. When the so-called “cold”-like symptoms appear in the initial stage of the disease, timely consultation is required for early detection, early diagnosis and early treatment. To prevent deterioration and inversion of the disease.