Japanese encephalitis (JE) is a disease transmitted by mosquitoes. People and many animals (livestock, poultry and birds) infected with JE virus can become the source of JE infection. JE is mainly transmitted by mosquito bites. Mosquitoes are not only the vectors of Japanese encephalitis virus, but also Japanese encephalitis virus can be transmitted through mosquito eggs in mosquitoes. Mosquitoes and pigs are the main long-term storage and diffusion hosts of this virus. In view of this, mosquito killing is one of the important measures to cut off the transmission route of Japanese encephalitis virus and prevent Japanese encephalitis. Another important measure to prevent Japanese encephalitis is to inject Japanese encephalitis vaccine to protect susceptible people from Japanese encephalitis virus infection.