title: Cell-free and cell-associated viremia in pigs after oronasal infection with Aujeszky's disease virus.
abstract: Nine pigs were examined for the presence of viremia during the first week after oronasal inoculation of 10(8.0) TCID50 Aujeszky's disease virus (ADV). Blood was taken at 1, 2, 3, 5 and 7 days post inoculation (PI) and the presence of cell-free ADV in plasma and of ADV-infected mononuclear cells was examined by titration and by cocultivation with permissive cells, respectively. The mononuclear cells of 6 of the 9 pigs, collected at 3 and 5 days PI were further separated into subpopulations of enriched monocytes and enriched lymphocytes. Both subpopulations were cocultivated. Nasal secretions were collected from 4 of the 9 pigs for the determination of virus titers and interferon concentrations. Both infected mononuclear cells and cell-free ADV were demonstrated in 5 pigs, infected mononuclear cells only were found in 2 pigs, and neither cell-associated or cell-free ADV were detected in 2 pigs. Two of the 7 viremic animals were positive on one single day, 3 on 2 days, 1 on 3 days and 1 on 4 days. The number of infected cells was approximately 5 times higher in monocytes than in lymphocytes. The highest virus titers were present in those nasal fluids with the lowest alpha-interferon concentration. A correlation between the titer of locally produced ADV in the nose and the presence of a viremia was not found. In conclusion, we can state that a viremia regularly occurs under both cell-free and cell-associated form after an oronasal inoculation of ADV and that monocytes are the most susceptible mononuclear cells.
authors.affiliation: Laboratory of Veterinary Virology, Faculty of Veterinary Medicine, University of Gent, Belgium.
authors.forename: H J
authors.initials: HJ
authors.lastname: Nawynck
authors.forename: M B
authors.initials: MB
authors.lastname: Pensaert
mesh_terms: D000818:Animals; D011558:Herpesvirus 1, Suid / Q000302:isolation & purification*; D007372:Interferons / Q000032:analysis; D007963:Leukocytes, Mononuclear / Q000821:virology; D017817:Nasal Lavage Fluid / Q000737:chemistry / Q000382:microbiology; D011557:Pseudorabies / Q000150:complications / Q000821:virology*; D013552:Swine; D013553:Swine Diseases / Q000821:virology*; D014766:Viremia / Q000662:veterinary* / Q000821:virology
chemical_list: D007372:Interferons