If petechiae appears after dog bite, and the surrounding area is red, swollen and painful, it is likely to get rabies. Rabies patients usually show symptoms such as irritability, fear of wind, water and light, and convulsions. The patient may eventually become paralyzed and in danger of death. In severe cases, there is an incubation period, usually about 3 months. In the initial stage, the patient may suffer from lack of energy, mild fever, headache, loss of appetite, etc., followed by fear of sound, light, wind, and pain, and numbness, itching, pain, and ant movement sensation in wounds that have healed. 1-2 days after the infection, the patient becomes sensitive to sounds. Slight stimulation can cause convulsions, irritability, thirsty and inability to drink, and extreme fear of water. Smelling of water, and seeing water, even talking about water may cause throat spasm, excessive sweating, salivation, and difficulty in urination and defecation. Paralysis, disappearance of fear, and cessation of convulsions may occur in the later period, but accompanied with indifferent expression, mouth that cannot be closed, weak breath, and unconsciousness. The prognosis is usually bad. Currently, there is no effective treatment methods for rabies, and the fatality rate of it is close to 100%. Therefore, prevention and vaccination are particularly important. If you are bitten by a dog, you should clean the wound thoroughly in time, and wash it thoroughly with 20% soapy water or 0.1% benzalkonium bromide (Syndactin) or other quaternary ammonium drugs to remove the virus remaining in the wound. This step is compatible with vaccines. Vaccination and passive immunization are equally important and cannot be ignored. Because soapy water can neutralize the effect of quaternary ammonium, the two cannot be used together. After washing, it is suggested to apply 75% ethanol or 2%-3% iodine. The wound should not be sutured, and the injured people should immediately inoculate rabies vaccine and immune serum.