Oral Presentation Australian Society for Fish Biology Conference 2018

Four common misconceptions about a potential carp biocontrol virus, and implications for a control program (#174)

Kenneth A McColl 1 , Agus Sunarto 1 , Matthew J Neave 1
  1. CSIRO-Australian Animal Health Laboratory, Geelong, VIC, Australia

There are four common misconceptions about the biology and use of cyprinid herpesvirus 3 (CyHV-3), a potential biocontrol agent for the common carp (Cyprinus carpio) in Australia. These will be discussed in the light of our earlier results, or planned studies.

Misconception # 1 is that CyHV-3 can infect, but not affect, a range of species in addition to carp. We have shown that the virus replicates in, and therefore infects, common carp only. # 2 suggests that genetic changes in the virus genome following release could possibly increase its host range. Lessons from evolutionary studies on herpesviruses, and from field observations with two different rabbit biocontrol viruses suggest otherwise. Misconception # 3 is that CyHV-3, alone, will be sufficient to control carp in Australia. Again, lessons from viral biocontrol of rabbits in Australia teach us that multiple broad-scale control measures will be required. Therefore, we have long-promoted the use of a genetic strategy to complement the effect of the virus. Finally, # 4 suggests that CyHV-3 can latently infect carp that survive infection. Although highly likely, this has not yet been proven. Differences between a persistent and a latent infection may be important in understanding the epidemiology of CyHV-3.