Eosinophil percentage 0.3 is slightly low. Low eosinophil percentage can be seen in normal cyclic fluctuations, but also in typhoid fever, after major surgery, etc. Eosinophils are a type of white blood cell called eosinophils because of the large number of eosinophilic granules in the cytoplasm of the cell when viewed under a microscope, and their normal range is 0.5% to 5% of the total number of white blood cells. Therefore, a percentage of 0.3 is on the low side. Under normal circumstances, the number of eosinophils in the blood also fluctuates periodically, with a low number in the morning and a high number at noon and in the afternoon, and if the decrease is generally not significant, other tests should be performed in this case. Eosinophils are also reduced in typhoid fever and in immunocompromise. Most often seen in typhoid fever, paratyphoid fever in the early stages, major surgery, burns and other stressful conditions, or after long-term use of adrenocorticotropic hormone, such cases of patients with immunocompromised, prone to eosinophil percentage of the phenomenon of low. Eosinophil percentage 0.3 may also be low for other reasons, it is recommended to go to the regular hospital, follow the doctor’s instructions to be targeted treatment.