Gao S, Luo J, Du J, Lang Y, Cong G, Shao J, Lin T, Zhao F, Belák S, Liu L, Chang H, Yin H.

Abstract:

Bovine viral diarrhea virus (BVDV) infects both domestic and wild animals, causing substantial economic losses. In order to investigate possible infection in Bactrian camels in Western China, a total of 56 blood samples were collected from clinically healthy Bactrian camels and tested for BVDV antigens and antibodies using antigen capture enzyme-linked immunosorbent assay (ELISA) and virus neutralization test. The antigen-positive samples (n=17) were further tested for viral nucleic acids by species-specific real-time RT-PCR assays, which showed presence of BVDV-1, but not BVDV-2 nor atypical bovine pestivirus, in the camel samples. Twelve non-cytopathogenic viruses were isolated and genetically typed by sequencing of the 5'untranslated region (5'UTR) and N(pro) coding sequences. Phylogenetic analysis divided the isolates into six known subgenotypes: BVDV-1a, BVDV-1b, BVDV-1c, BVDV-1m, BVDV-1o, BVDV-1p and a putative subgenotype, BVDV-1q. This study provides, for the first time, serological and molecular evidence for natural infection of Bactrian camels in Western China with highly divergent BVDV-1 strains. Further investigations are needed to elucidate the possible roles of Bactrian camels in the epidemiology of BVD in Western China.