For patients with sudden high fever, and headache, body aches and other symptoms, they should go to a nearby regular hospital outpatient clinic for detailed examination in a timely manner, and ask the doctor to determine the cause of the symptoms based on the examination results, and then take active treatment. Patients are not recommended to take medication without authorization to avoid delaying their condition.1. Infectious diseases: Patients may be caused by common cold virus, influenza virus or bacterial infection, etc. Symptoms vary in severity and generally have fever, headache, accompanied by sore throat, cough, runny nose, sneezing and other symptoms, and those with severe symptoms may also have joint pain in the limbs, weakness, dizziness and other symptoms. Patients need to consult a doctor promptly and take body temperature, check blood routine and C-reactive protein and other tests, and if necessary, do influenza virus pathogenic tests, which can be used for timely diagnosis and differential diagnosis based on the results, and then take cause-specific treatment measures, including the use of antibiotics such as levofloxacin, azithromycin, roxithromycin, or antiviral drugs such as oseltamivir and zanamivir under the guidance of a doctor, together with physical or antipyretic drugs such as ibuprofen and acetaminophen for comprehensive treatment; 2. Systemic diseases: immune disorders, tumors, hematologic diseases, etc., can cause sudden high fever and symptoms such as headache and generalized aches and pains. Patients must promptly consult a doctor to clarify the diagnosis after CT, MRI, routine blood tests and other examinations. Patients with immune disorders can be treated with medications such as pidomod dispersible tablets or oral thymidine enteric-coated tablets under the guidance of a doctor. Patients with tumors and hematological diseases can be treated with radiotherapy, chemotherapy or surgery. For patients who have not found a clear cause, it is not recommended to take antipyretic and analgesic drugs such as ibuprofen and acetaminophen without authorization.