Development of reverse transcription loop-mediated isothermal amplification assays to detect Hantaan virus and Seoul virus

We developed two assays based on one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP) to identify Hantaan virus (HTNV) and Seoul virus (SEOV), members of the Hantavirus genus that cause hemorrhagic fever with renal syndrome (HFRS). Our results showed that these assays can be conducted within 30 min under isothermal conditions. The detection limit for HTNV was around 10 copies per reaction, similar to detection levels for quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays. The detection limit for SEOV was 100 copies per reaction, a sensitivity that was 10-fold lower than that for qRT-PCR assays but 10-fold higher than that for RT-PCR assays. The method we developed was specific for both HTNV and SEOV without any cross-reaction with other pathogens. We conclude that RT-LAMP assays could be useful for the rapid and direct detection of HTNV and SEOV clinically, and for the epidemiological investigation of HFRS.