Myxomatosis and Rabbit Haemorrhagic Disease
There are two very serious viral diseases in rabbits that are common in unvaccinated rabbits: myxomatosis and rabbit haemorrhagic disease (RHD). This was previously known as viral haemorrhagic disease, or VHD.
There is now a known variant of RHD called RHD2 which is fatal to rabbits. A vaccine became available in January 2017. The Rabbit Welfare Association report that we can expect RHD2 to become more common than the original strain over the next five years.
From 5 weeks of age – Vaccination against myxomatosis and RHD is carried out once a year and covers both diseases. This should be done as soon as possible upon acquiring a new rabbit.
From 10 weeks of age – It is now possible to vaccinate against RHD2 with a separate vaccination which needs to be given two weeks apart from the Myxo/RHD vaccination. Again this is done once a year.
We would therefore suggest that in youngsters we give the Myxo-RHD vaccination between 5 and 8 weeks of age, then the RHD2 vaccination at 10 weeks of age.
In adult rabbits the vaccinations can be given in any order, at any time, as long as the minimum gap of 2 weeks is left between the injections.
Occasionally a small reaction can occur at the injection site but this is insignificant when compared to the disease seen in unvaccinated animals.
Myxomatosis is caused by the myxoma virus, which is widely distributed in the wild rabbit population.
You might think that your rabbit never comes into contact with wild rabbits and so does not need vaccination but unfortunately this is not the case; myxomatosis is spread by biting insects such as fleas and mosquitoes so can be carried many miles from an infected rabbit to your pet.
The incubation period of the disease is two days to a week and the first sign is often the development of
- puffy eyelids
- pus-producing conjunctivitis
- swelling spreading to the mouth, ears and genital region.
Death usually occurs two to three weeks after infection.
Rabbit Haemorrhagic Disease (RHD)
RHD (previously known as VHD) has an almost world-wide distribution and is being seen more and more in the UK.
The disease is caused by a calicivirus and, although the incubation period is up to three days, animals may die suddenly without any outward symptoms.
If there are signs they may include;
- There may be convulsions
- difficulty breathing
- foaming at the mouth
- profuse bleeding from the nose.
Some rabbits survive the initial period but die a few weeks later of liver failure. Veterinary surgeons rarely see rabbits with RHD as they die so quickly at home that they never make it to the veterinary surgery.
myxomatosis is still the most prevalent of viral rabbit diseases
RHD2 is caused by a virus similar to one we are already familiar with, which causes RHD (rabbit haemorrhagic disease). The original Myxo/RHD vaccine does not protect against this new strain.
Both variants of the RHD virus can be spread easily, as it can survive for long periods outside of the body and resists extended periods of temperatures up to 50ºC, meaning it can be spread on shoes/clothing and will survive washing machine cycles. Reportedly the virus can also be spread in the faeces of predators and scavengers that have eaten infected rabbits.
It is worth remembering that despite all the media coverage and concern over this new disease, that myxomatosis is still the most prevalent of viral rabbit diseases and is common in this area, and also that the original strain of RHD is still the most common of the two viral haemorrhagic diseases. It is therefore essential that your rabbit’s standard vaccination is up to date.