The clinical manifestations of encephalitis are complex and varied, primarily caused by infections from pathogens such as viruses and bacteria. There are numerous clinical symptoms, with fever being quite common; patients generally exhibit significant fevers, which can reach up to 38 degrees Celsius or even as high as 40 degrees Celsius. Headache is also a very common clinical manifestation of encephalitis, with some patients experiencing severe headaches accompanied by pronounced nausea and vomiting. Additionally, some patients may exhibit psychiatric symptoms, which mainly include incoherent speech, hallucinations, and failing to recognize family members. Some patients may experience cognitive impairments, such as diminished memory, and significant deficits in computational and judgment abilities. In severe cases, some patients may have epileptic seizures, characterized by convulsions of the limbs. Overall, the manifestations of encephalitis are diverse and can range from simple fever and headache to severe conditions such as psychiatric symptoms, cognitive impairments, and epilepsy.