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Japanese Encephalitis Vaccine Licensed (1992)

Japanese Encephalitis is a mosquito-borne viral encephalitis found in Asia. Most infections are asymptomatic, but the disease is fatal in 30 percent of people who develop illness.

A Japanese-manufactured vaccine was licensed in the United States in 1992. Among the significant contributions to licensure were clinical trials for efficacy conducted by the U.S. Army Medical Research and Materiel Command in Thailand and Hawaii.

The vaccine is used to protect military personnel traveling or deploying to eastern Asia and the western Pacific islands.