Recurrent fever accompanied by some cold symptoms (cough, sore throat, general weakness, aching limbs, etc.) is often a sign of low body immunity and a weak cold. If you have recurrent fever accompanied by weight loss, memory loss, anemia, and weakness, you need to exclude malignant tumors, tuberculosis, immune diseases, infectious diseases (such as AIDS), etc. Fever is actually a response of the human body to external resistance and is clinically common in various infectious diseases, such as respiratory tract infections (pneumonia, bronchitis), gastroenteritis, urinary tract infections, etc. Tuberculosis patients also have recurrent low-grade fever, and the specific causative organism can be basically clarified through blood sampling and laboratory tests. Some allergic diseases, such as drug fever, rheumatic fever, allergy, etc., also present recurrent fever. Some malignant tumors and hematological diseases, such as common leukemia, colon cancer, and primary liver cancer, can also present with recurrent fever. In addition, certain infectious diseases (such as AIDS, brucellosis, etc.) can also present with recurrent fever. Fever involves a wide range of diseases. For fever of unknown origin, it is important not to use antipyretic drugs blindly, and it is recommended to use physical cooling until the cause is identified.