Comparison of reverse transcription loop-mediated isothermal amplification, conventional PCR and real-time PCR assays for Japanese encephalitis virus.

We developed and evaluated a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for detecting Japanese encephalitis virus (JEV). The sensitivity of the JEV RT-LAMP assay was in concordance with that of real-time RT-PCR and 10-fold more sensitive than that of conventional RT-PCR, which the detection limit was 24 copies/μl. The JEV RT-LAMP was highly specific, which no cross-reactivity was found with dengue-2 virus, rabies virus, norovirus, astrovirus and human enterovirus 71. The JEV RT-LAMP assay was more simple and less time-consuming compared to the conventional RT-PCR and real-time RT-PCR, which the amplification could be completed in a single tube within 1 h under isothermal conditions at temperature of 63°C. The results suggest that the RT-LAMP assay can be applied as a practical molecular diagnostic tool for JEV infection and surveillance.