The causes of persistent fever in children mainly include the following: 1, caused by children suffering from influenza, after children suffer from influenza, if they do not apply anti-influenza virus drugs such as oseltamivir in time, it will often cause persistent fever in children, and the fever is mostly high. 2, caused by children suffering from Kawasaki disease, children suffering from Kawasaki disease will have persistent fever, and will be accompanied by 3. Children with EBV infection, which can cause infectious mononuclear cell hyperplasia, resulting in persistent fever, enlarged liver and spleen, and enlarged lymph nodes in the neck.