Morpholino oligomers are single stranded DNA analogues containing same nitrogenous bases as DNA but joined by backbone consisting of morpholine rings and phosphorodiamidate linkages [16] . For efficient delivery into cells these Morpholino are often conjugated with arginine rich peptide [17] . However, in the current study we have used a different type of Morpholino oligomer called Vivo-Morpholino against 39CSI and one of the secondary structures present in 59 UTR of the JEV genome. Vivo-Morpholino are specialized type of non-peptide Morpholino oligomers, conjugated with a new transport structure that provides effective delivery into a wide variety of tissues in living animals, thereby raising the possibilities of their use as therapeutic agents. The transporter comprises of a dendritic structure assembled around a triazine core which serves to position eight guanidinium head groups in a conformation effective to penetrate cell membranes. Vivo-Morpholinos have also been shown to effectively enter and function within cultured cells [18] . Vivo-Morpholinos are also cost effective, non immunogenic, and stable under physiological conditions as compared to other types of Morpholinos. This study was designed to evaluate whether the use of Vivo-Morpholinos as therapeutic agents, is possible in an experimental model of JE. We intend to show that these specifically designed Vivo-Morpholinos are effective in countering the viral load in the body, thereby imparting significant protection to the animals that were infected with a lethal dose of JEV.