Referential diagnostic techniques to analyze virulence markers of pseudorabies virus RC/79 strain: preliminary assays

Abstract

The indirect immunoperoxidase and immunofluorescence methods were standardized for the detection of Aujeszky's disease virus in Vero cell cultures, using as a model the RC/79 strain virus."

There was a strong correlation in the results obtained by both methods. The results proved to be highly specific for the identification of the virus and allowed a precise localization of the viral antigen in infected cells. The presence of syncytia with a strong reaction in the nuclear region 16 hours p.i. indicated that RC/79 strain is strongly virulent. This conclusion was supported by the results obtained from experimental rabbit infection. The animals were inoculated with different doses of the virus (10²-10⁵ PFU). In all the cases the mortality rate was 100%, even when animals received minor doses of the virus, indicating no dose response. The mean death time was 62 and 120 hours p.i. for the different doses used. Between 6 and 24 hours prior to death, all rabbits presented an exudative lesion in the inoculation area and extensive pruritus.

The methods employed were useful as virulence markers of the RC/79 strain virus and on the other hand, they constitute essential tools in the diagnosis of Aujeszky's disease virus.