Encephalitis is an infectious disease of the central nervous system caused by viruses, bacteria, and other pathogens that directly invade the brain cells, causing an inflammatory response in the brain parenchyma. There are several types of encephalitis, and the severity of different types of encephalitis varies.1. Mild encephalitis: Viral encephalitis is generally a common viral infection that causes mild symptoms and is less severe, and has a better prognosis with aggressive antiviral therapy. In addition, the symptoms of bacterial encephalitis are also mild, but the condition can be aggravated by the development of septic encephalitis without timely treatment; 2. Severe encephalitis: such as some tuberculous encephalitis, septic encephalitis and spirochete encephalitis, the symptoms are generally severe, patients will have fever, headache, convulsions, impaired consciousness, etc., and the condition can be severe with hemiplegic weakness, seizures, brain abscess, brain herniation, etc., endangering the life safety. For young children, the ability to resist the disease is low due to their young age and poor health. If the disease is not detected in its early stages and is not treated correctly, the aggravation of encephalitis may cause more serious consequences, threatening life safety and even death. Patients with encephalitis are advised to go to a regular hospital for timely related examinations. Clinically, lumbar puncture is usually required to test the cerebrospinal fluid for pathogens, cell counts, and proteins. After the diagnosis is clear, timely treatment such as anti-infection, cranial pressure lowering and brain cell nutrition is performed, while attention is paid to strengthening care and preventing complications.