Perspectives on molecular detection methods of lyssaviruses.

Lyssaviruses belong to the family Rhabdoviridae within the order Mononegavirales. Their genomes consist of a negative stranded linear RNA. Although dog transmitted rabies causes the majority of the estimated 55 000 worldwide fatalities per year, bat lyssaviruses have also caused human cases. Based on a broad range of different host species, their geographical distribution and the evolutionary age lyssaviruses display a high degree of genetic variability. Thus the development of molecular diagnostics for the reliable detection and identification of members of the genus Lyssavirus (pan-lyssavirus assay) is a challenge, but is valuable for the fight against rabies worldwide. In this study different published PCR-systems or primers for the detection of a wide range of lyssaviruses were tested as real-time RT-PCRs with different one-step and two-step assays. Comparison of different two-step assays by varying the RT-chemistry revealed differences in sensitivity. Nevertheless, most of the tested one-step systems provided an improved performance, including a reduced assay time and a reduced risk of cross-contaminations, when compared to the optimized two-step assay. Finally, we also provide an overview of additional state-of-the-art molecular methods to detect and differentiate lyssavirus species in general.