Health Heroes - Valneva

Japanese Encephalitis Virus Is Potentially Fatal. Consult a Healthcare Professional About Risks. Video Editor - Euan James-Richards Japanese Encephalitis is a potentially fatal disease caused by the JE virus, which is spread by mosquitoes. JE virus is the main cause of viral encephalitis in many Asian countries. Around the world, there are about 68,000 cases of JE each year.