How to distinguish bacteria and viruses in fever blood routine?

During fever, bacterial infection and viral infection can be preliminarily distinguished by indicators such as white blood cell count, neutrophil ratio, and lymphocyte ratio in blood routine. Bacterial infections usually manifest as an increase in white blood cells and neutrophils, while viral infections often have normal or decreased white blood cells accompanied by an increase in lymphocyte proportion. But the final diagnosis needs to be comprehensively judged based on clinical symptoms and other examinations. The blood routine characteristics of bacterial infection include a total white blood cell count exceeding the normal range, a significantly increased proportion of neutrophils, and possible left shift of the nucleus. inflammatory markers such as C-reactive protein and procalcitonin are often significantly elevated. This type of infection is more common when pathogens such as Streptococcus pneumoniae and Staphylococcus aureus invade, and patients often exhibit symptoms such as chills and purulent secretions. Commonly used antibiotics in clinical practice include cefuroxime granules, amoxicillin and clavulanate potassium tablets, levofloxacin tablets, etc. The blood routine of viral infection often shows normal or mildly reduced white blood cell count, relatively increased lymphocyte proportion, and the possibility of atypical lymphocytes. When infected with pathogens such as EB virus and influenza virus, the proportion of monocytes may increase. These patients usually have systemic symptoms such as sore throat and muscle pain, but rarely have purulent manifestations. The treatment should focus on symptomatic treatment, such as Lianhua Qingwen Capsules, Oseltamivir Granules and other antiviral drugs. It is important to note that the misuse of antibiotics in viral infections may exacerbate drug resistance.

Blood routine testing should be performed 12-24 hours after fever, and early examination may not reflect the true inflammatory state. The blood routine changes in infants, elderly people, and immunocompromised individuals may not be typical. When the results are at a critical value or the clinical manifestations do not match, it is recommended to repeat the testing and complete serological, pathogen culture, and other examinations. Daily attention should be paid to recording the type of fever, accompanying symptoms, and medication reactions. When seeking medical treatment, providing a detailed medical history to the doctor can help accurately determine the type of infection.