Fever after the 13-valent pneumonia vaccine may be caused by an adverse reaction to the vaccine and usually requires no treatment. It may also be caused by an upper respiratory tract infection, which can be treated with medication to relieve the symptoms. It is recommended to consult a doctor in time to clarify the cause of the disease. 1. Adverse reaction: Fever after vaccination may be caused by the adverse reaction after vaccination. Because in the process of vaccine injection into the body to produce antibodies, the symptoms of fever may occur, this situation generally do not need treatment, can be relieved by themselves, and the fever generally does not exceed 38.5 ℃. 2. Upper respiratory tract infection: Fever after vaccination may be caused by upper respiratory tract infection. Upper respiratory tract infection is a general term for acute inflammation of the nasal cavity, pharynx or larynx. Common pathogens are viruses, and only a few are caused by bacteria. Patients can follow the doctor’s instructions to use medication, drugs include acetaminophen, aspirin, ribavirin, oseltamivir, levofloxacin, moxifloxacin, jimmy falciparum and so on. If you feel unwell, you should go to the hospital in time to avoid delaying your condition or causing adverse reactions.