Blood counts are not a diagnostic criterion for pneumonia, nor can blood count results be used to determine what type of pneumonia a patient has. In patients with severe infectious pneumonia, blood counts may be normal if the patient is normally immunocompromised. However, most people with infectious pneumonia, blood routine suggests increased white blood cells and neutrophils, which can be used as an indicator of the severity of the infection, but it is not absolute. Patients with lung CT suggesting pneumonia and upper respiratory symptoms such as cough and fever should be given broad-spectrum antibiotics based on clinical presentation and pathogenetic testing, even if the blood count is normal. In addition to routine blood tests, there are other indicators of infection, such as calcitoninogen, C-reactive protein, blood sedimentation, etc., to comprehensively determine the patient’s condition, and standardize the treatment according to the relevant tests.