Whether an infant with low white blood cells should be hospitalized after the fever has gone down depends on the severity of the disease. If the low white blood cells are caused by medication or exposure to radioactive radiation, the white blood cells can gradually return to normal after stopping the medication or removing the triggering factors, and hospitalization is generally not necessary, and regular rechecks of blood counts can be performed. If the degree of low white blood cells is more serious, it may be caused by infection, and severe sepsis may occur. If the low white blood cells are caused by aplastic anemia or leukemia, it is necessary to be hospitalized for systematic treatment. It is recommended that under the guidance of the doctor, according to the specific condition of the child, to take targeted treatment.