First identification and phylogenetic analysis of equine hepacivirus in Korea.
Non-primate hepacivirus (NPHV) corresponds a group of isolates recently characterized in horses and dogs that present similar genomic organization and are closely related to hepatitis C virus. Since canine hapacivirus, NPHV identified in dogs, was first discovered in dogs in the United States, equine hepacivirus (EqHV, NPHV identified in horses) has been identified in horses in several countries. However, no epidemiological studies have investigated EqHV in horses in Korea. In this study, a total of 74 (n=74) serum samples collected from horses in four regions of Korea were tested for EqHV RNA using nested RT-PCR. Overall, 14 samples were identified as positive (18.9%) and further analyzed according to gender, age, breed, and region. There were high positive rates in males, young horses, and Thoroughbreds; however, these rates differed regionally. Sequencing of the partial NS3 region of 12 samples and the polyprotein encoding regions of two samples positive for EqHV RNA revealed that the Korean EqHV isolates shared approximately 85.3-99.6% and 97.7-100% homology at the nucleotide and deduced amino acid level, respectively. Phylogenetic analysis revealed that the partial NS3 genes clustered with sequences previously reported as NPHV. Notably, sequences of EqHV detected in horses in the same region showed sequence divergence. The sequences of the polyprotein encoding region of two representative EqHVs shared 83.9% and 95.7% homology with each other at the nucleotide and deduced amino acid level, respectively. Comparison of the sequences of polyprotein encoding regions of Korean EqHV isolates and hepaciviruses from different hosts revealed that the NS3 and NS5B regions were most conserved among hepaciviruses. The results of the present study demonstrate that there is a high positive rate of EqHV in Korea and provide significant information regarding the geographical distribution and genetic variability of Korean EqHV isolates that will help improve global epidemiology of EqHV.
Laboratory of Veterinary Microbiology, College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon, Republic of Korea.
Ho-Seong
HS
Kim
Laboratory of Veterinary Microbiology, College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon, Republic of Korea.
Hyun-Woo
HW
Moon
Laboratory of Veterinary Microbiology, College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon, Republic of Korea.
Haan Woo
HW
Sung
Laboratory of Veterinary Microbiology, College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon, Republic of Korea. Electronic address: kwonhm@kangwon.ac.kr.
Hyuk Moo
HM
Kwon
D000818:Animals; D001483:Base Sequence; D017124:Conserved Sequence; D005260:Female; D016174:Hepacivirus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D006526:Hepatitis C / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D006734:Horse Diseases / Q000453:epidemiology* / Q000821:virology; D006736:Horses / Q000821:virology; D008297:Male; D010802:Phylogeny; D012367:RNA, Viral / Q000097:blood; D056910:Republic of Korea / Q000453:epidemiology; D017422:Sequence Analysis, DNA; D017361:Viral Nonstructural Proteins / Q000235:genetics*; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases; D012324:RNA-Dependent RNA Polymerase
D012367:RNA, Viral; D017361:Viral Nonstructural Proteins; C084422:NS3 protein, hepatitis C virus; D012697:Serine Endopeptidases; D043583:Nucleoside-Triphosphatase; D053487:DEAD-box RNA Helicases; D000085242:Viral Proteases; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase
Equine hepacivirus (EqHV); Hepacivirus; Hepatitis C virus; Horses; Molecular detection; Nonprimate hepacivirus