Calicivirus in Rabbits

Is your pet rabbit up to date with his or her vaccinations against Calicivirus?

Calicivirus RHDV1

The original Calicivirus (RHDVl) was released in Australia in 1996 as a biological control measure to help reduce wild rabbit populations. Alongside the release of the virus, a vaccination was made available to provide protection for pet rabbits. The virus has become less effective in killing wild rabbits over time and a new strain of Calicivirus, called KS, is being prepared for release most likely in autumn 2016.

Calicivirus can cause sudden death in pet rabbits, or you might see fever, restlessness or lethargy followed by a decrease in appetite and/or a bloody discharge from the nose.

The current vaccine available for protection against Calicivirus is effective against the KS strain if rabbits have received their annual booster. The Australian Veterinary Association recommends that rabbits are vaccinated against Calicivirus at 10-12 weeks and then annually. Rabbits may be vaccinated earlier than 10 weeks but then a booster is recommended 4 weeks later. 

Calicivirus RHDV2

In addition to KS, another Calicivirus that affects rabbits, called RHDV2, is now circulating in Australia. RHDV2 causes the same symptoms as the other strains of Calicivirus but is a distinctly separate virus and the current vaccine is less effective in providing protection against it. This disease first appeared in France in 2010 and has since spread around the world, appearing in Canberra in May 2015. This new strain of the virus doesn't pose any threat to humans, but it causes a high death rate in rabbit kittens (3-4 weeks old) and even some vaccinated adults. Until a more effective vaccine has been developed, young rabbits can be vaccinated at 4 weeks, 8 weeks and 12 weeks of age and then yearly, although this use of the vaccine is currently "off label".


Myxomatosis, another rabbit virus spread by mosquitoes and fleas, is also currently circulating in the Goulburn Valley area. This virus causes swollen eyes, ears, nose and genital region, and rabbits will often be snuffling and sneezing. There is no vaccine available in Australia for this disease and the only way to prevent rabbits becoming infected is to stop them being bitten by mosquitoes. Pet rabbits are very susceptible to Myxomatosis and suffer greatly with the disease. Euthanasia is recommended if they become infected.