Most of the preventive injections are biochemical preparations, and fever is likely to occur after injection into the body. If the fever is mild and low, it does not need to be treated, you can drink more water to promote sweating in the body, which can relieve. However, if the body temperature rises and is greater than 38.5°C, prompt treatment is required. You can choose antipyretic drugs, for example, acetaminophen syrup can be used to bring down the body temperature quickly. During this period, it is also important to take the temperature 2-3 times a day and observe the change of temperature. In case of recurrent low-grade fever, it is also important to control the infection with anti-inflammatory drugs to avoid co-infection with bacteria. It is also important to observe the child’s wound site. If there is a wound infection, it is also likely to cause recurrent low-grade fever. If infection is identified, local disinfection should be performed in order to bring relief.