title: Serological and molecular evidence of hepadnavirus infection in swine.
abstract: OBJECTIVE
  Recently, investigations in a swine herd identified evidence of the existence of a novel member of the Hepadnavirus family endemic in swine. The aim of this study was to investigate the serological and molecular markers of Hepadnavirus circulation in Brazilian domestic swine and wild boar herds, and to evaluate the identity with HBV and other Hepadnaviruses reported previously.
  
  
  METHODS
  For the study, 376 swine were screened for hepatitis B virus serological markers. Analyses were performed in serum samples using commercial enzyme-linked immunosorbent assay (ELISA) kits (DiaSorin®) for anti-HBc, HBsAg and anti-HBs. Reactive and undetermined swine serum samples were selected to perform DNA viral extraction (QIAamp DNA Mini Kit, Qiagen®), partial genome amplification and genome sequencing.
  
  
  RESULTS
  From 376 swine samples analysed, 28 (7.45%) were reactive to anti-HBc, 3 (0.80%) to HBsAg and 6 (1.6%) to anti-HBs. Besides, more 17 (4.52%) swine samples analyzed were classified in the grey zone of the EIA test to anti-HBc and 2 (0.53%) to HBsAg. From 49 samples molecularly analyzed after serological trial, 4 samples showed a positive result for the qualitative PCR for Hepadnavirus. Phylogenetic reconstruction using partial genome sequencing (360 bp) of 3 samples showed similarity with HBV with 90.8-96.3% of identity.
  
  
  CONCLUSIONS
  Serological and molecular data showed evidence of the circulation of a virus similar to hepatitis B virus in swine.
authors.affiliation: Laboratory of Development Technological in Virology, Oswaldo Cruz Institute, FIOCRUZ, RJ, Brazil.
authors.forename: Yasmine R
authors.initials: YR
authors.lastname: Vieira
authors.affiliation: Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, FIOCRUZ, RJ, Brazil.
authors.forename: Marcelle F M
authors.initials: MF
authors.lastname: Silva
authors.affiliation: Departament of Veterinary Microbiology and Immunology, Federal Rural University of Rio De Janeiro, UFRRJ, RJ, Brazil.
authors.forename: Débora R L
authors.initials: DR
authors.lastname: Santos
authors.affiliation: Departament of Animal Production, Institute of Animal Science, Federal Rural University of Rio De Janeiro, UFRRJ, RJ, Brazil.
authors.forename: Antônio A
authors.initials: AA
authors.lastname: Vieira
authors.affiliation: Brazilian National Research Center, EMBRAPA Swine and Poultry, SC, Brazil.
authors.forename: Janice R
authors.initials: JR
authors.lastname: Ciacci-Zanella
authors.affiliation: Tropical Sustainability Institute, TSI, SP, Brazil.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Barquero
authors.affiliation: Laboratory of Molecular Virology, Oswaldo Cruz Institute, FIOCRUZ, RJ, Brazil.
authors.forename: Bárbara V
authors.initials: BV
authors.lastname: do Lago
authors.affiliation: Laboratory of Molecular Virology, Oswaldo Cruz Institute, FIOCRUZ, RJ, Brazil.
authors.forename: Selma A
authors.initials: SA
authors.lastname: Gomes
authors.affiliation: Laboratory of Development Technological in Virology, Oswaldo Cruz Institute, FIOCRUZ, RJ, Brazil.
authors.forename: Marcelo A
authors.initials: MA
authors.lastname: Pinto
authors.affiliation: Laboratory of Development Technological in Virology, Oswaldo Cruz Institute, FIOCRUZ, RJ, Brazil.
authors.forename: Vanessa S
authors.initials: VS
authors.lastname: de Paula
mesh_terms: D000818:Animals; D001938:Brazil / Q000453:epidemiology; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D006510:Hepatitis B Antibodies / Q000032:analysis; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D017422:Sequence Analysis, DNA / Q000662:veterinary; D013552:Swine; D013553:Swine Diseases / Q000453:epidemiology* / Q000821:virology; D014764:Viral Proteins / Q000235:genetics
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D014764:Viral Proteins