title: No transmission of hepatitis E virus in pigs fed diets containing commercial spray-dried porcine plasma: a retrospective study of samples from several swine trials.
abstract: BACKGROUND
  Hepatitis E virus (HEV) has been reported in the human population and pigs are a recognized reservoir for HEV and a possible source of HEV transmission to humans. Spray-dried porcine plasma (SDPP) is an ingredient commonly used in feed for pigs around the world. Even though processing conditions used to produce SDPP should be adequate to inactivate HEV, it was of interest to analyze commercial SDPP samples for presence of genome and antibodies (AB) against HEV and to retrospectively analyze serum samples collected from pigs used in past experiments that had been fed diets containing either 0% or 8% SDPP to detect potential transmission of HEV as determined by seroconversion.
  
  
  RESULTS
  Eighty-five commercial SDPP samples were analyzed by ELISA and 100% of them contained AB against HEV, while 22.4% (11 of 49 samples analyzed) were positive for HEV RNA. Frozen sera samples (n = 140) collected from 70 pigs used in past experiments that had been fed diets containing either 0% or 8% commercial SDPP was analyzed by ELISA for AB against HEV. Age of pigs at sera sampling ranged from 3 to 15 weeks and feeding duration of diets ranged from approximately 4 to 9 weeks. One lot of SDPP used in one experiment was analyzed and confirmed to contain HEV RNA. Regardless of the diet fed, some sera samples collected at the beginning of an experiment contained AB titer against HEV. These sera samples were collected from weaned pigs prior to feeding of the experimental diets and the HEV titer was probably from maternal origin. However, by the end of the experiments, HEV titer was not detected or had declined by more than 50% of the initial titer concentration.
  
  
  CONCLUSIONS
  To our knowledge, this is the first study reporting presence of HEV AB titer and RNA in SDPP. Retrospective analysis of serum collected from pigs fed diets with SDPP revealed no indication of seroconversion to HEV. The results indicate that feeding SDPP in diets for pigs does not represent a risk of transmitting HEV, even though HEV genome may be detected in SDPP.
authors.affiliation: Centre de Recerca en Sanitat Animal (CReSA), Fundación UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain. Joan.pujols@cresa.uab.cat.|Institut de Recerca i Tecnologia Agroalimentàries (IRTA), Barcelona, Spain. Joan.pujols@cresa.uab.cat.
authors.forename: Joan
authors.initials: J
authors.lastname: Pujols
authors.affiliation: APC EUROPE, S.A. Avda, Sant Julià 246-258, Pol. Ind. El Congost, E-08400, Granollers, Spain. Carmen.rodriguez@ampc-europe.com.
authors.forename: Carmen
authors.initials: C
authors.lastname: Rodríguez
authors.affiliation: Centre de Recerca en Sanitat Animal (CReSA), Fundación UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain. Nuria.navarro@cresa.uab.cat.
authors.forename: Nuria
authors.initials: N
authors.lastname: Navarro
authors.affiliation: Centre de Recerca en Sanitat Animal (CReSA), Fundación UAB-IRTA, Campus de la Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain. Sonia.pina@cresa.uab.cat.
authors.forename: Sonia
authors.initials: S
authors.lastname: Pina-Pedrero
authors.affiliation: APC Inc., 2425 SE Oak Tree Court, Ankeny, IA, 50021, USA. Joy.campbell@functionalproteins.com.
authors.forename: Joy M
authors.initials: JM
authors.lastname: Campbell
authors.affiliation: APC Inc., 2425 SE Oak Tree Court, Ankeny, IA, 50021, USA. joe.crenshaw@functionalproteins.com.
authors.forename: Joe
authors.initials: J
authors.lastname: Crenshaw
authors.affiliation: APC EUROPE, S.A. Avda, Sant Julià 246-258, Pol. Ind. El Congost, E-08400, Granollers, Spain. javier.polo@ampc-europe.com.|APC Inc., 2425 SE Oak Tree Court, Ankeny, IA, 50021, USA. javier.polo@ampc-europe.com.
authors.forename: Javier
authors.initials: J
authors.lastname: Polo
mesh_terms: D000821:Animal Feed / Q000821:virology*; D000818:Animals; D004032:Diet / Q000379:methods*; D005517:Foodborne Diseases / Q000662:veterinary* / Q000821:virology; D006508:Hepatitis Antibodies / Q000032:analysis; D016751:Hepatitis E / Q000635:transmission / Q000662:veterinary* / Q000821:virology; D016752:Hepatitis E virus / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D010949:Plasma / Q000821:virology*; D012367:RNA, Viral / Q000032:analysis; D012189:Retrospective Studies; D017422:Sequence Analysis, DNA; D044967:Serum / Q000276:immunology / Q000821:virology; D013552:Swine; D013553:Swine Diseases / Q000635:transmission* / Q000821:virology
chemical_list: D006508:Hepatitis Antibodies; D012367:RNA, Viral