Objective: To construct infectious Japanese encephalitis virus (JEV) based on the in vitro-ligated cDNA template of the vaccine strain SA14-14-2, and identify the virus.
Methods: Full-length genomic cDNA of JEV SA14-14-2 strain was ligated and then RNA was transcribed in vitro, the infective virus was obtained by transfecting the RNA into Vero cells and identified.
Results: The infective clone of JEV was constructed, the virulence was weaker than the wild virus.
Conclusion: It was possible to construct infectious clone from the production strain of live attenuated Japanese B encephalitis vaccine.