Rabbit Calicivirus (RHD: Rabbit Haemorrhagic Disease Virus)

Calicivirus in Australia

There are three main strains of rabbit calicivirus causing disease in Australia: the original virus, a Korean strain and a European strain. The original virus has been present here since 1995. The Korean strain is similar to the original virus and is planned to be released here in Autumn 2017.  The European strain has been present in Australia since 2015.  

RHDV1 – original strain (present in Australia since 1995) 

RHDV1 – K5 (Korean strain)

RHDV2 – (European strain)

Vaccination

The Cyclap vaccine provides protection against the original virus and the Korean strain. It was not developed to protect against the European strain, but it might provide partial protection because there are some similarities between the viruses. 

To improve the amount of protection the Cyclap vaccine provides against the European strain, the Australia Veterinary Association recommends a new vaccination protocol for rabbits. This protocol might provide better protection, but so far there have been no studies to support this. In addition, it is an ‘off-label’ use of the vaccine in that the pharmaceutical company has not tested or recommended to use the vaccine in this way and are not liable for any problems that may result.  

The new recommendations as follows: 

Kittens: 4, 8, 12 weeks of age, then 6 monthly for life

Adults: 2 vaccinations 1 month apart, then 6 monthly for life

Possible side effects from the vaccine are lethargy, reduced appetite or skin reactions around the site of injection. You should contact your vet if you notice any of these. 

Transmission 

The viruses can be transmitted by direct contact with infected rabbits, objects infected rabbits have contacted and by some insects such as flies. If you have had a rabbit with suspected calicivirus you should discuss a cleaning protocol with your vet before introducing new rabbits to your home. 

Disease

The European strain affects younger rabbits than the other strains. It may cause disease as early as 3-4 weeks old. Symptoms may be present for 3-5 days before death and include:  

  • fever
  • seizures
  • weakness
  • pale mucous membranes 

If you have a rabbit suspected of having calicivirus, the Australian Veterinary Association recommends your vet performs an autopsy to confirm the diagnosis. This will help you ensure no new rabbits you obtain contract the virus and may help provide evidence for or against the new vaccination protocol.  

Rabbit