Patients with anemia do not usually develop fever. The cause of anemia is usually caused by the lack of raw materials for hematopoiesis. Iron deficiency, vitamin B12 deficiency, and folic acid can cause the manifestation of anemia. In this case, it is recommended to go to the hospital for further examination to clarify the cause of the fever, to clarify the cause, and to carry out active treatment for the cause and symptoms.