title: Serological and Molecular Detection of Senecavirus A Associated with an Outbreak of Swine Idiopathic Vesicular Disease and Neonatal Mortality.
abstract: We performed a longitudinal field study in a swine breeding herd that presented with an outbreak of vesicular disease (VD) that was associated with an increase in neonatal mortality. Initially, a USDA Foreign Animal Disease (FAD) investigation confirmed the presence of Senecavirus A (SVA) and ruled out the presence of exotic agents that produce vesicular lesions, e.g., foot-and-mouth disease virus and others. Subsequently, serum samples, tonsil swabs, and feces were collected from sows (n = 22) and their piglets (n = 33) beginning 1 week after the onset of the clinical outbreak and weekly for 6 weeks. The presence of SVA RNA was evaluated in all specimens collected by reverse transcriptase quantitative PCR (RT-qPCR) targeting a conserved region of the 5' untranslated region (5'-UTR). The serological response (IgG) to SVA was evaluated by the weekly testing of sow and piglet serum samples on a SVA VP1 recombinant protein (rVP1) indirect enzyme-linked immunosorbent assay (ELISA). The rVP1 ELISA detected seroconversion against SVA in clinically affected and non-clinically affected sows at early stages of the outbreak as well as maternal SVA antibodies in offspring. Overall, the absence of vesicles (gross lesions) in SVA-infected animals and the variability of RT-qPCR results among specimen type demonstrated that a diagnostic algorithm based on the combination of clinical observations, RT-qPCR in multiple diagnostic specimens, and serology are essential to ensure an accurate diagnosis of SVA.
authors.affiliation: College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA luisggl@iastate.edu.
authors.forename: Luis Gabriel
authors.initials: LG
authors.lastname: Gimenez-Lirola
authors.affiliation: College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
authors.forename: Chris
authors.initials: C
authors.lastname: Rademacher
authors.affiliation: College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Linhares
authors.affiliation: College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
authors.forename: Karen
authors.initials: K
authors.lastname: Harmon
authors.affiliation: College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
authors.forename: Marisa
authors.initials: M
authors.lastname: Rotolo
authors.affiliation: Department of Statistics, College of Liberal Arts and Sciences, Iowa State University, Ames, Iowa, USA.
authors.forename: Yaxuan
authors.initials: Y
authors.lastname: Sun
authors.affiliation: College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
authors.forename: David H
authors.initials: DH
authors.lastname: Baum
authors.affiliation: College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Zimmerman
authors.affiliation: College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
authors.forename: Pablo
authors.initials: P
authors.lastname: Piñeyro
mesh_terms: D000818:Animals; D004196:Disease Outbreaks; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005243:Feces / Q000821:virology; D007074:Immunoglobulin G / Q000097:blood; D008137:Longitudinal Studies; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D014066:Palatine Tonsil / Q000821:virology; D010849:Picornaviridae / Q000302:isolation & purification*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012698:Serologic Tests / Q000379:methods*; D044967:Serum / Q000821:virology; D013552:Swine; D013555:Swine Vesicular Disease / Q000175:diagnosis* / Q000453:epidemiology*
chemical_list: D007074:Immunoglobulin G