A positive blood culture is a positive blood culture when a patient has a fever, especially when the body temperature exceeds 38°C, or when there is severe chills or chills, the patient’s peripheral blood is drawn and placed in a blood culture bottle for aerobic or anaerobic culture, and if there is colony growth, the blood culture is positive. A positive blood culture means that pathogenic microorganisms are present in the blood, and the specific culture of pathogenic microorganisms and drug sensitivity tests are very important for the clinical treatment of infections. For patients with unexplained fever, especially high fever, combined with chills and chills, blood culture must be taken as early as possible and the results of blood culture should be noted. If the blood culture is positive, according to the clinical symptoms and other laboratory tests, determine whether it is the causative organism and give anti-infection treatment as soon as possible, it will have obvious benefits for the control of the patient’s infection and the prognosis of the patient’s disease.