In infants and children with persistent low-grade fever, it is important to first identify the cause of the fever and treat the cause to be effective. The main cause of hypothermia in infants and young children is infection, including bacterial, viral, mycoplasma or mycobacterial infections. If the fever lasts for a short period of time, not more than a week, it is mostly due to viral infection, and can be treated with antiviral Chinese medicines, such as Pudilan Oral Liquid and Blue Scutellaria Oral Liquid. In case of influenza virus, oseltamivir can be used. Persistent low fever can also be seen in bacterial infections, especially lymphadenitis, urinary tract infections, etc. Cephalosporin antibiotics, such as cefixime, can be used orally. If it is clear that the infection is mycoplasma, oral azithromycin is required. Persistent low fever for more than a week should be noted to exclude tuberculosis and hematologic diseases, and requires a thorough examination at the hospital.