Fever from DPT vaccination may be caused by adverse reactions to vaccination, or by cold and upper respiratory tract infection. 1. Adverse reaction of vaccination: DPT vaccine is a combined vaccine used to prevent pertussis, diphtheria and tetanus. After vaccination, it will cause the body to produce immune response and protective antibodies, which may cause fever, local redness and swelling and other adverse reactions, but most of them will be relieved in 2~3 days, and no special treatment is needed. 2. Cold: the body’s resistance is relatively low after vaccination, the child after vaccination due to cold and other factors, it will lead to fever. 3. Upper respiratory tract infection: the body’s resistance may be lower after vaccination, which may easily cause viruses and bacteria to invade the respiratory tract, resulting in fever symptoms, accompanied by sneezing, nasal congestion and other manifestations. When your child is vaccinated with DPT and has fever, parents are advised to take their children to the hospital in time.