title: Prevalence of the Novel Torque Teno Sus Virus Species k2b from Pigs in the United States and Lack of Association with Post-Weaning Multisystemic Wasting Syndrome or Mulberry Heart Disease.
abstract: The family Anelloviridae includes a number of viruses infecting humans (Torque teno viruses, TTV) and other animals including swine (Torque teno sus viruses, TTSuV). Two genetically distinct TTSuV species have been identified from swine thus far (TTSuV1 and TTSuVk2), although their definitive association with disease remains debatable. In 2012, a novel TTSuV species was identified from commercial swine serum and classified in the genus Kappatorquevirus as TTSuVk2b. The other Kappatorquevirus species, TTSuVk2a, has been associated with post-weaning multisystemic wasting syndrome (PMWS) when coinfected with porcine circovirus type 2 (PCV2). Therefore, in this study, we initially amplified a portion of TTSuVk2b ORF1 and, subsequently, assessed the molecular prevalence of the virus in pigs in the United States. A total of 127 serum and 115 tissue samples were obtained from pigs with PMWS or mulberry heart disease (MHD) in six states and tested by PCR for the presence of TTSuVk2b DNA. Approximately 27.6% of the serum and 21.7% of tissue samples tested positive for TTSuVk2b DNA, and the positive products were confirmed by sequencing. However, we did not detect a correlation between TTSuVk2b infection and PMWS or MHD. The near full-length genomic sequence of US TTSuVk2b was determined, and sequence analysis revealed that the US TTSuVk2b isolates were 95% identical to the TTSuVk2b isolate from Spain, with most of the variations clustering in ORF1. We conclude that the novel TTSuVk2b species is present in pigs in the United States and its potential association with a disease warrants further investigation.
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
authors.forename: A J
authors.initials: AJ
authors.lastname: Rogers
authors.affiliation: College of Animal Sciences, Zhejiang University, Hangzhou, China.
authors.forename: Y-W
authors.initials: YW
authors.lastname: Huang
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
authors.forename: C L
authors.initials: CL
authors.lastname: Heffron
authors.affiliation: The Roslin Institute, University of Edinburgh, Midlothian, Edinburgh, UK.
authors.forename: T
authors.initials: T
authors.lastname: Opriessnig
authors.affiliation: Boehringer Ingelheim Vetmedica Inc, Ames, IA, USA.
authors.forename: A R
authors.initials: AR
authors.lastname: Patterson
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.
authors.forename: X-J
authors.initials: XJ
authors.lastname: Meng
mesh_terms: D000818:Animals; D060085:Coinfection / Q000662:veterinary; D004266:DNA Virus Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D016757:Death, Sudden, Cardiac / Q000453:epidemiology / Q000662:veterinary*; D006321:Heart / Q000821:virology; D006331:Heart Diseases / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D008099:Liver / Q000821:virology; D010802:Phylogeny; D053570:Porcine Postweaning Multisystemic Wasting Syndrome / Q000453:epidemiology* / Q000821:virology; D015995:Prevalence; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology* / Q000821:virology; D022783:Torque teno virus / Q000235:genetics / Q000302:isolation & purification*; D014481:United States / Q000453:epidemiology; D014811:Vitamin E Deficiency / Q000453:epidemiology / Q000662:veterinary / Q000821:virology
keywords: Torque teno sus virus k2b; mulberry heart disease; post-weaning multisystemic wasting syndrome