title: Isolation and phylogenetic analysis of orf virus from the sheep herd outbreak in northeast China.
abstract: BACKGROUND
  Orf is a zoonotic and epitheliotrophic contagious disease that mainly affects sheep, goats, wild ruminants, and humans with a worldwide distribution. To date, there is little information on the characterization of ORFV strains that are endemic in Mainland China. In addition, the relationship between the severity of disease and the molecular profile of ORFV strains has not been fully elucidated.
  
  
  RESULTS
  From the recent outbreak of a sheep herd in Nongan, northeast of China, the novel orf virus (ORFV) strain NA1/11 was successfully isolated. Western blot analysis indicated that the NA1/11 strain cross reacts with monoclonal antibody A3 and infected sheep ORFV antiserum. The purified virions revealed the typical ovoid shape when observed by atomic force microscopy. To determine the genetic characteristics of the NA1/11 strain, the sequences of ORFV011 (B2L), ORFV059 (F1L), ORFV109, ORFV110 and ORFv132 (VEGF) genes were amplified and compared with reference parapoxvirus strains. Non-metric multidimensional scaling (nMDS) was performed to analyze the nucleotide similarities between different ORFV strains.
  
  
  CONCLUSIONS
  Phylogenetic analysis based on ORFV 011 nucleotide sequences showed that the NA1/11strain was closely related to Xinjiang and Gansu strains. ORFV110 and ORFV132 genes are highly variable. The results revealed that precise phylogenetic analysis might provide evidence for genetic variation and movement of circulating ORFV strains in Northeast China. In addition, nMDS analysis showed that geographic isolation and animal host are likely major factors resulting in genetic differences between ORFV strains.
authors.affiliation: Institute of Antibody Engineering, School of Biotechnology, Southern Medical University, N, Guangzhou Avenue 1838, Guangzhou 510515, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Zhangyong
authors.initials: Z
authors.lastname: Ning
authors.forename: Wenbo
authors.initials: W
authors.lastname: Hao
authors.forename: Deguang
authors.initials: D
authors.lastname: Song
authors.forename: Feng
authors.initials: F
authors.lastname: Gao
authors.forename: Kui
authors.initials: K
authors.lastname: Zhao
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Liao
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Rock
authors.forename: Shuhong
authors.initials: S
authors.lastname: Luo
mesh_terms: D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western / Q000662:veterinary; D002681:China / Q000453:epidemiology; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D004196:Disease Outbreaks / Q000662:veterinary*; D004474:Ecthyma, Contagious / Q000453:epidemiology / Q000821:virology*; D018625:Microscopy, Atomic Force / Q000662:veterinary; D046529:Microscopy, Electron, Transmission / Q000662:veterinary; D008969:Molecular Sequence Data; D009923:Orf virus / Q000235:genetics / Q000302:isolation & purification* / Q000648:ultrastructure; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D012756:Sheep; D014771:Virion / Q000648:ultrastructure; D015047:Zoonoses / Q000453:epidemiology / Q000821:virology*
chemical_list: D004279:DNA, Viral