Rapid detection of European orthobunyaviruses by reverse transcription loop-mediated isothermal amplification assays

Abstract

Abstract: The development of reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assays are described herein for the detection of two orthobunyaviruses (Bunyaviridae), which represent the two main serogroups found in mosquitoes in Central Europe. The RT-LAMP assays were optimized for the detection ofˇTahyˇna virus (a California encephalitis group virus found in Aedes sp or Ochlerotatus spmosquitoes) and Batai virus (also called ˇCalovo virus, a Bunyamwera group virus found in Anopheles maculipennis s.l. mosquitoes) nucleic acid using endemic European virus isolates. The sensitivity of the RT-LAMP assays was determined to be comparable to that of conventional tests, with a limit of detection < 0.1pfu per reaction. The assays can be performed in 60 min under isothermal conditions using very simple equipment. Furthermore, it was possible to proceed with the assays without nucleic acid extraction, albeit at a 100-fold loss of sensitivity. The RT-LAMP assays are a sensitive, cost-efficient method for both arbovirus surveillance as well as diagnostic laboratories to detect the presence of these endemic orthobunyaviruses.