Rabbit calicivirus disease is a highly infectious, fatal disease that affects wild and pet European rabbits. Caliciviris will often break out in springtime and vaccination against this fatal disease is imperative.
The virus probably originated from a less severe form present in rabbit populations for many years. It was first reported in China in 1984 and soon after in other countries in Asia and Europe and in Mexico. These reports alerted scientists to a potentially new biological control for wild rabbits in Australia and New Zealand. The virus was taken into quarantine at the CSIRO Australian Animal Health Laboratory in Geelong for comprehensive testing over three years from June 1991. During fields trials in 1995 it escaped from Wardang Island, South Australia. The virus swept across the Flinders Ranges through the arid zone and killed large numbers of rabbits.
Ten million rabbits were killed within 8 weeks of its escape!
The virus is spread by direct contact with infected rabbit or infected objects. The virus may also be carried by the wind or by flies, fleas, and mosquitoes. The virus can hang around in infected areas for up to 200 days!
Calicivirus mostly infects adult rabbits. Young rabbits less than 8 weeks of age can be temporarily resistant to the virus. The incubation period for the Calicivirus virus is between 1 to 3 days, with death following 1 to 2 days after the infection.
There is a wide range of Calicivirus symptoms although most rabbits will show no signs and simply die suddenly. Rabbits with Calicivirus may display fevers, restlessness, lethargy and poor appetite. They may have a bloody discharge from the nose and blood-stained cage floors may be noticed. Rabbits who have recovered from the less severe symptoms usually go on to develop liver disease with weight loss and lethargy. Diarrhoea, constipation and tummy pain are they die a few weeks later L. However the more typical picture is one of a sudden, unexpected death.
There is no treatment for Calicivirus infection.
Some wild rabbits will survive infection and thus the population of feral rabbits continues to be problem in the Australian bush. Unfortunately, our pet rabbits are very susceptible to the disease and are very unlikely to survive infection. The death rate in pet rabbits is almost 100%.
So what can we do to protect our beloved pet bunnies?
Fortunately there is a vaccine available. Rabbits less than 12 weeks are given one injection followed by a booster one month later. Rabbits over 12 weeks of age are given a single dose of vaccine. Vaccination must then be continued every six months for life. The vaccine offers very good immunity and is essential for protection of all pet rabbits. Reducing contact with wild rabbits and controlling mosquitoes and fleas in your rabbit’s environment is also very important. Revolution top spot can be used monthly to control fleas.
By following these simple guidelines and making sure your rabbit is vaccinated every six months you can ensure good protection against this otherwise fatal disease. If your rabbit is not up to date with vaccination, or you are not sure, please call and schedule an appointment. When it comes to Calicivirus infections – there is no cure, only prevention and it is very VERY important to stay up to date!