Japanese Encephalitis

Schedule: JE vaccine is recommended for children (2 months of age and older) and adults at increased risk of Japanese encephalitis during travel to Asia. The vaccine is given as a 2-dose series, with the doses spaced 28 days apart. The second dose should be given at least 1 week before travel. A booster dose of JE vaccine may be given to anyone who was vaccinated more than one year ago and is still at risk of exposure, or might be re-exposed.

Japanese Encephalitis (JE) virus is the leading cause of vaccine-preventable encephalitis in Asia and the western Pacific. For most travelers to Asia, the risk for JE is very low but varies based on destination, duration of travel, season, and activities. JE virus is maintained in a cycle involving mosquitoes and vertebrate hosts, mainly pigs and wading birds. Humans can be infected when bitten by an infected mosquito. Most human infections are asymptomatic or result in only mild symptoms. However, a small percentage of infected persons develop inflammation of the brain (encephalitis), with symptoms including sudden onset of headache, high fever, disorientation, coma, tremors and convulsions. About 1 in 4 cases are fatal. There is no specific treatment for JE. Patient management focuses on supportive care and management of complications. Steps to prevent JE include using personal protective measures to prevent mosquito bites and vaccination.

Websites:

CDC website offers resources and information on the Japanese Encephalitis vaccine.

Vaccines.gov provides resources from federal agencies for the general public and their communities about vaccines across the lifespan.

Children’s Hospital of Philadelphia provides questions and answers about Japanese Encephalitis from the Vaccine Education Center.

Immunization Action Coalition offers free information and downloads for healthcare providers, coalitions, and parents.