When should someone get the japanese encephalitis virus vaccine?

Travellers to Asia: Certain travellers to asia should get the vaccine and some lab workers who may have increased risk of exposure to the virus. If you are planning travel to asia then check out the cdc website for travel related info and meet with your md or a travel clinic for further information

These conditions:: Risks are very low but seek advice if traveling to rural se asia for a month or more especially if extensive nighttime or outdoor activity. Risk rises notably if near rice paddies or pig farms. The virus life cycle depends on wading birds and pigs (humans are accidental hosts) in these conditions the usual risk rate 1/million is more substantial. Go to travel clinic.