Genetic heterogeneity among parapoxviruses isolated from sheep, cattle and Japanese serows (Capricornis crispus).

Standard strains of four parapoxviruses and seven unclassified Japanese strains isolated from sheep, cattle and wild Japanese serows (Capricornis crispus) were compared molecularly. Restriction fragment length polymorphism (RFLP) analysis of viral DNA, indirect immunofluorescence assays using monoclonal antibodies, partial nucleotide sequencing of the envelope gene, phylogenetic analysis and PCR-RFLP were carried out. These analyses revealed that the parapoxviruses were divided into four groups and the region sequenced in this study was highly conserved within each group. Each of the Japanese isolates was classified into one of these groups. These findings also indicated that parapoxvirus infections among wild Japanese serows seem to be caused by at least two different parapoxviruses, bovine papular stomatitis virus and orf virus. The methods presented here are useful for genetic characterization and classification of parapoxviruses.