Phylogenetic analysis of three orf virus strains isolated from different districts in Shandong Province,East China

Orf virus (ORFV) is the causative agent of contagious ecthyma, which is a zoonoticdisease that affects sheep, goats, wild small ruminants and humans. Shandong Province inEast China is one of the main producing areas in China for sheep and goats. Here, weconducted epidemiological surveys in different areas in this Province, isolated three orfvirus strains, SDLC, SDTA and SDJN, from goat flocks and then analyzed the geneticevolution of these strains. The ORFV011, ORFV059,ORFV109, ORFV110 and ORFV127 genes of thesethree strains were amplified, sequenced and analyzed. Phylogenetic analysis showed thatORFV011 of the SDLC and SDTA strains cluster together with the Gansu,Liaoning, Shanxi, Nantou, Hoping and FJ-YX strains, while SDJN clusters with the FJ-GS andFJ-GO strains. ORFV059 of the SDLC and SDTA strains cluster together withthe FJ-YX strain, while SDJN clusters with the FJ-GS and FJ-GO strains.ORFV059 and ORFV127 of these three strains weresimilar to those of the OV-SA00 strain. The results suggested that SDLC, SDTA and SDJNoriginated from Fujian Province and formed a complex group of viruses in ShandongProvince. As the role of ORFV127 gene responsible for the immune evasionof ORFV, the pathogenesis of these three virus strains may similar to that of OV-SA00.These three strains first isolated in Shandong Province are novel ORFV strains, and thedata reported here will be helpful for further research about ORFV and its comprehensiveprevention and control.