When a fever occurs after vaccination, it is usually below 38.5°C. This is because vaccination is artificial active immunity, i.e., vaccines are administered to the body through immunization, thereby prompting the body to develop specific immunity, similar to the process of mimicking the occurrence and development of a disease. After vaccination of healthy people, the body may show similar disease manifestations, with fever being the most common symptom. In general, no special treatment is needed for such fevers, which can be gradually relieved by keeping warm and drinking plenty of fluids. However, it should be noted that fever after vaccination may also be caused by other diseases. If, in addition to fever, a patient has cough, runny nose, sneezing, dizziness and other symptoms after vaccination, the symptoms may be due to an acute upper respiratory tract infection, or cold, and may not be related to vaccination. In addition to antipyretic and analgesic drugs, antibiotics can be given under the guidance of a doctor if necessary. At the same time, attention should be paid to ensuring rest, enhancing nutrition, drinking more water and eating a light diet, which can promote the improvement of the disease. Therefore, under normal circumstances, the fever caused by vaccination can disappear in about 3 days, but if the fever persists or exceeds 38.5℃, it needs to be treated promptly. If the fever persists or exceeds 38.5℃, it needs to be treated promptly. You can contact the doctor of the vaccination unit and follow the medical advice to cool down physically or give antipyretic and analgesic drugs such as ibuprofen and acetaminophen to cool down the fever.