Encephalitis B is prevalent during the seasons, mainly summer and fall. The full name of Encephalitis B is epidemic encephalitis B. In the past, it was called Japanese encephalitis B, and its pathogen is the encephalitis B virus. This pathogen is mainly distributed in Asia, and the main way of transmission is through mosquito bites, so in the mosquito season, summer and fall are the main seasons of Encephalitis B epidemics. Patients infected by mosquito bites with encephalitis B virus will be directly infected with the central nervous system because of the strong neurophilic nature of the virus, leading to the onset of encephalitis B. Patients with acute onset of the disease will have high fever. Patients with acute onset, with high fever, impaired consciousness, often accompanied by convulsions, manifested as tonic spasmodic seizures, which belong to symptomatic epilepsy, and positive signs of meningeal irritation on examination. If the treatment is not timely enough, the condition is more serious, and the cure often leaves serious sequelae.