Studies on co-infection of Peste des petits ruminants virus and orf virus In vitro

In peste des petits ruminants (PPR) affected goat/sheep flocks the most commonly occurring mixed viral infection is orf. Hence the present study was aimed to study the interaction of PPR virus (PPRV) and orf virus by co-infecting both the viruses in vitro using Vero cells. Both the PPRV field isolate and orf virus field isolate, adapted in Vero cells were utilized for co-infection. Equal quantum of both the viruses (100 CCID50) was used for all the three methods of co-infection (Initial infection with PPRV virus followed by orf virus, Initial infection with orf virus followed by PPR Virus and Simultaneous infection with both the PPR virus and orf virus). Three types of control i.e. PPRV infected Vero cells, orf infected Vero cells and uninfected Vero cells were maintained. In all the three types of co-infection of PPRV and orf virus, the results revealed only the establishment of PPRV infection in Vero cells which was detected even at 5th passage whereas, the co-infected orf virus was not detected after second passage. Both the orf virus and PPRV were detected in all the five passages of their virus control Vero cells infected separately with respective viruses. The PPRV has dominated the co-infected orf virus and established the infection even at 5th passage in Vero cells.