Development of a SYBR Green–based RT-qPCR assay for the rapid detection of peste-des-petits-ruminants virus

Peste-des-petits-ruminants (PPR) is primarily a disease of small ruminants caused by peste-des-petits-ruminants virus (PPRV; <i>Paramyxoviridae</i>, <i>Morbillivirus caprinae</i>), formerly the small ruminant morbillivirus. PPRV can cause significant morbidity and mortality in small ruminants and a significant economic impact. Conventional reverse-transcription PCR (RT-PCR), and probe-based and SYBR Green-based RT quantitative real-time PCR (RT-qPCR), are employed for the molecular detection of PPRV. Here we describe a SYBR Green-based RT-qPCR for rapid and sensitive detection of PPRV. We designed the specific primers from the conserved region of the fusion gene (<i>F</i>) of PPRV. The standard curve of the established RT-qPCR assay had a good linear relationship. The developed assay was also 3 log units more sensitive than the conventional RT-PCR, with a detection limit of 13.6 copies and an efficiency of 98.2%. There was no cross-reactivity with other caprine respiratory viruses, namely bluetongue virus, goatpox virus, and orf virus. The positive detection rate of clinical samples was 11 of 64 (17.2%) versus 10 of 64 (15.6%) by conventional RT-PCR. We confirmed our results by sequencing the full <i>F</i> and <i>N</i> genes of the isolates. Our SYBR Green RT-qPCR can be used as a fast, economical, and sensitive alternative to RT-PCR for the detection of PPRV.