title: A novel pathogenic Mammalian orthoreovirus from diarrheic pigs and Swine blood meal in the United States.
abstract: Since May 2013, outbreaks of porcine epidemic diarrhea have devastated the U.S. swine industry, causing immense economic losses. Two different swine enteric coronaviruses (porcine epidemic diarrhea virus and Delta coronavirus) have been isolated from the affected swine population. The disease has been reported from at least 32 states of the United States and other countries, including Mexico, Peru, Dominican Republic, Canada, Columbia, Ecuador, and Ukraine, with repeated outbreaks in previously infected herds. Here we report the isolation and characterization of a novel mammalian orthoreovirus 3 (MRV3) from diarrheic feces of piglets from these outbreaks in three states and ring-dried swine blood meal from multiple sources. MRV3 could not be isolated from healthy or pigs that had recovered from epidemic diarrhea from four states. Several MRV3 isolates were obtained from chloroform-extracted pig feces or blood meal in cell cultures or developing chicken embryos. Biological characterization of two representative isolates revealed trypsin resistance and thermostability at 90°C. NextGen sequencing of ultrapurified viruses indicated a strong homology of the S1 segment to mammalian and bat MRV3. Neonatal piglets experimentally infected with these viruses or a chloroform extract of swine blood meal developed severe diarrhea and acute gastroenteritis with 100% mortality within 3 days postinfection. Therefore, the novel porcine MRV3 may contribute to enteric disease along with other swine enteric viruses. The role of MRV3 in the current outbreaks of porcine epidemic diarrhea in the United States remains to be determined, but the pathogenic nature of the virus warrants further investigations on its epidemiology and prevalence.
  
  
  OBJECTIVE
  Porcine orthoreoviruses causing diarrhea have been reported in China and Korea but not in the United States. We have isolated and characterized two pathogenic reassortant MRV3 isolates from swine fecal samples from porcine epidemic diarrhea outbreaks and ring-dried swine blood meal in the United States. These fecal and blood meal isolates or a chloroform extract of blood meal induced severe diarrhea and mortality in experimentally infected neonatal pigs. Genetic and phylogenetic analyses of two MRV3 isolates revealed that they are identical but differed significantly from nonpathogenic mammalian orthoreoviruses circulating in the United States. The present study provides a platform for immediate development of suitable vaccines and diagnostics to prevent and control porcine orthoreovirus diarrhea.
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
authors.forename: Athmaram
authors.initials: A
authors.lastname: Thimmasandra Narayanappa
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
authors.forename: Harini
authors.initials: H
authors.lastname: Sooryanarain
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
authors.forename: Jagadeeswaran
authors.initials: J
authors.lastname: Deventhiran
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
authors.forename: Dianjun
authors.initials: D
authors.lastname: Cao
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
authors.forename: Backiyalakshmi
authors.initials: B
authors.lastname: Ammayappan Venkatachalam
authors.affiliation: Center for Viticulture and Small Fruits, Florida A&M University, Tallahassee, Florida, USA.
authors.forename: Devaiah
authors.initials: D
authors.lastname: Kambiranda
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
authors.forename: Tanya
authors.initials: T
authors.lastname: LeRoith
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
authors.forename: Connie Lynn
authors.initials: CL
authors.lastname: Heffron
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
authors.forename: Nicole
authors.initials: N
authors.lastname: Lindstrom
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
authors.forename: Karen
authors.initials: K
authors.lastname: Hall
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Jobst
authors.affiliation: Livestock Veterinary Services, Kinston, North Carolina, USA.
authors.forename: Cary
authors.initials: C
authors.lastname: Sexton
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA.
authors.forename: Xiang-Jin
authors.initials: XJ
authors.lastname: Meng
authors.affiliation: Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA kumarans@vt.edu.
authors.forename: Subbiah
authors.initials: S
authors.lastname: Elankumaran
mesh_terms: D000818:Animals; D001769:Blood / Q000821:virology*; D016000:Cluster Analysis; D003967:Diarrhea / Q000662:veterinary* / Q000821:virology; D005243:Feces / Q000821:virology*; D012089:Mammalian orthoreovirus 3 / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D013552:Swine; D013553:Swine Diseases / Q000821:virology*; D014481:United States; D014776:Virus Cultivation
chemical_list: D012367:RNA, Viral