Title: Experimental co-infection of chickens and turkeys with avian influenza and newcastle disease viruses Authors
|Cha, Ra Mi|
Submitted to: American Association of Avian Pathologists
Publication Type: Abstract Only
Publication Acceptance Date: March 1, 2013
Publication Date: July 20, 2013
Citation: Pantin Jackwood, M.J., Miller, P.J., Afonso, C.L., Spackman, E., Kapczynski, D.R., Shepherd, E.M., Smith, D.M., Cha, R., Swayne, D.E. 2013. Experimental co-infection of chickens and turkeys with avian influenza and newcastle disease viruses [abstract]. American Association of Avian Pathologists Meeting, July 20-23,2013, Chicago, IL. CDROM. Technical Abstract: Avian influenza virus (AIV) and Newcastle disease virus (NDV) are the two most important viruses affecting poultry worldwide. Co-infections of poultry with AIV and NDV are a problem from both the clinical point of view and the diagnosis of these viruses. The goal of this study was to examine the interaction between AIV and NDV in infected poultry species. We conducted experiments in which we infected chickens and turkeys with lentogenic, mesogenic or velogenic strains of NDV, and with low pathogenicity (LP) or high pathogenicity (HP) AIV, as relevant to specific ecosystems, by giving the viruses simultaneously or sequentially. Pathogenesis (clinical signs, lesions), presence of the viruses in tissues, duration and titer of virus shedding for each virus, transmission to contact birds, and seroconversion to both viruses was evaluated. Chickens co-infected with a lentogen NDV vaccine strain (LaSota) and a LPAIV responded similarly to infection as chickens infected with the viruses given separately; however an effect on virus shedding was observed in co-infected birds. In turkeys, previous exposure to LPAIV prevented infection with NDV. More importantly, previous infection of chickens with mesogenic or velogenic NDV interfered with HPAIV infection, but the virulence of the NDV strain and the timing of HPAIV inoculation affected the outcome of infection. In conclusion, previous or simultaneous infection of NDV and AIV can interfere with the replication dynamics and the disease caused by these viruses in poultry.