Simultaneous Detection and Identification of Peste des petits ruminants Virus Types Ⅱ and Ⅳ by MCA-Based Real-Time RT-qPCR Assay within Single Reaction

Peste des petits ruminants (PPR) disease is a cross-species infectious disease that severely affects small ruminants and causes great losses to livestock industries in various countries. Distinguishing vaccine-immunized animals from naturally infected animals is an important prerequisite for the eradication of PPR. [ ](javascript:void(0);)Although peste des petits ruminants virus (PPRV) was currently divided into lineages I-IV and only one vaccine strain N75 belongs to type II, its epidemic strains in China all belong to lineage IV. As to achieve this goal, we developed an SYBR Green I real-time RT-qPCR method for rapid detection and differentiation of PPRV lineage II and IV by analyzing different melting curve analyses. Primers targeting the L gene were highly specific, as evidenced by the negative amplification of closely related viruses, such as Orf virus, goat poxvirus, and Foot-and-mouth disease virus. The sensitivity of the assay was assessed based on plasmid DNA and the detection limit achieved was 10 copies of PPRV-II and PPRV-IV respectively. As the method has high sensitivity, specificity, and reproducibility, which will be significant in effectively controlling the occurrence and transmission of PPRV.