Viruses or other biological control methods can have significant negative animal welfare impacts on target and non-target species. Viruses and biological controls such as rabbit haemorrhagic disease virus (RHDV) can severely impact animal welfare due to prolonged fever, loss of appetite, lethargy, and fatigue prior to death. Infected rabbits may experience rapid respiration, bloody discharge from the nose, convulsions, paralysis, and squealing.

SPCA is concerned about the potential for unforeseen and negative consequences from biological control methods for humans, animals, and the environment. SPCA is concerned with the use of contagious viral mechanisms to facilitate temporary or permanent sterilisation due to the unintended spread to non-target animals.

If biological control methods deployed to control an animal population can impact companion or farmed animals, then owners should be notified with adequate time to take protective measures (including vaccinations) for their pets or farmed animals prior to any proposed release.