Rabbit Calicivirus – New Strain

Autumn 2017 brings the controlled release of a new strain of Rabbit Calicivirus, the K5 strain of RHDV1 (Rabbit Haemorrhagic Disease Virus 1). This is on top of the recent outbreak strain of Calicivirus – RHDV2 that has been identified in and around the ACT, in the last couple of years.

There are some very important points to understand about these viruses. K5 is a variant of the original strain of RHDV1. It is being deliberately released into the wild rabbit population because the original virus has become less effective over time. RHDV2 is a European variant of the Calicivirus. It is not known how it came to be present in Australia.

Current vaccination against the original RHDV1 virus IS effective against K5. This means that pet rabbits up to date with Calicivirus vaccination will be protected against K5. However, our current vaccination provides only partial protection against RHDV2.

Thus we are recommending that pet rabbits get two vaccinations initially one month apart then a booster vaccination every 6 months to give full protection against both strains of RHDV1 (and as much protection as possible against RHDV2). A vaccine for RHDV2 is under development in Europe but is some time off. When available be sure that we will notify everyone ASAP!

It is also strongly recommended that rabbits are kept in insect proof enclosures or inside as a further measure to reduce the risk of contracting either Calicivirus or Myxomatosis.

If you have any concerns or questions or are worried about your bunny please call and we can help. Remember, the most important thing you can do is make sure your rabbit remains up to date with vaccination every 6 months.


Read more on the Australian Veterinary Association website, or in an article published on the ABC online news site.