Cytopathic effect of PPR vaccine virus strains in Vero cells

The present study describes the cytopathic effect of two different Peste des petits ruminants (PPR) vaccine virus strains presently being used in the country, in vero cells. The cytopathic effect (CPE) was visible from 4th day post infection in Sungri vaccine virus strain where as Arasur vaccine virus strain showed CPE, 36-48 hr post infection. With both vaccine virus strains the CPE in vero cells showed initial cell rounding, aggregation and syncytial development. The generalized CPE was noticed by 6th day in Sungri and by 96 hrs post infection in Arasur strain. However complete detachment of the cell monolayer was observed in Arasur strain by 120 hr, post infection. Infected coverslip cultures stained with H & E and May & Grunwaldʹs Giemsa showed cell vaculation, cytoplasmic extension and syncytia comprising of five to six nuclei. Acidophilic intracytoplasmic and intranuclear inclusion bodies were also observed. Titers, HA activity and detection by s-ELISA of both the vaccine virus strains are also compared