Encephalitis. Japanese encephalitis is the leading cause of encephalitis in asia with 30, 000-50, 000 cases/year. I.
Age? According to the cdc website, previous jev vaccine for kids 1-17 is no longer available. The existing vaccine is for kids & adults >17. See: wwwnc. Cdc. Gov/travel/page/child-travel. Htm.
Also. Cdc notes doctor may choose to administer vaccine off-label in children less than 17 years of age. As of february 2013, Ixiaro approved for use in all of europe for children aes 2 months & up, maybe paving the way for use in the usa soon for children. In your child's case unless vacation is for a month in rural area w/ pigs and rice paddies & lots of outdoor time, vaccine not needed.