There are several highly infectious and potentially fatal diseases that can affect your rabbit. Fortunately, vaccines have been produced that will protect your rabbit against two of these – myxomatosis and viral haemorrhagic disease. To ensure that your rabbit is fully protected it is essential that it receives regular booster injections.
Vaccines are given by injection under or into the skin in rabbits. They all work by training the white blood cells in your rabbit’s body how to recognise and attack the viruses or bacteria contained in the vaccine. This should prevent infection with that particular bug if your rabbit is in contact with it again. Current vaccines fall into two main categories: ‘live vaccines’ which contain a strain of the bug which has been altered so that it cannot cause disease but does stimulate immunity, and ‘dead vaccines’ in which the bug has been killed by heat or chemicals. Each type has their pros and cons – live vaccines generally give better and longer-lasting protection but they can sometimes cause more side-effects. Live vaccines are not recommended for certain groups of rabbits, such as pregnant females.
Myxomatosis is a disease caused by a virus. It only affects rabbits, but both wild rabbits and pet rabbits are susceptible. The virus causes severe swelling of the lips, eyelids and genitals. Wild rabbits suffering from this condition usually fall victim to predators, eg foxes, or are hit by cars. Pet rabbits can sometimes recover from the condition with very intensive nursing, but most are euthanased.
The virus causing myxomatosis is transmitted between infected and healthy rabbits by insects, particularly rabbit fleas, but also by flies. Cats often become infected by rabbit fleas and will bring these into your garden or inside your house. Therefore, even if your rabbit lives indoors or if you live in a city centre, far from places where wild rabbits live, your pet rabbit could still be at risk.
Viral haemorrhagic disease (VHD or HVD) is a horrible viral condition that only affects rabbits. It is caused by a highly contagious virus which is transmitted from rabbit to rabbit, or on contaminated equipment, clothing and feed. Insects, rodents and birds may also be able to carry the virus and infect isolated rabbits (such as pet rabbits). VHD is nearly always fatal – it causes massive bleeding (haemorrhage) from the internal organs and the animals die as a result of the overwhelming blood loss.
Rabbits can be vaccinated against myxomatosis from 6 weeks of age. It is generally a seasonal disease – although it can occur all year round, the numbers of cases peak significantly in the late summer/early autumn. The vaccination provides immunity for one year and so vaccination in May or June is best. In high-risk areas, such as East Anglia where there are high numbers of wild rabbits with the disease, or if you live close to area where wild rabbits live, it is advisable to have your rabbit vaccinated twice a year for maximum protection.
Your rabbit can be vaccinated against VHD when it reaches 2.5-3 months old. It then requires a booster injection every year. In the event of an outbreak of VHD, baby rabbits can be vaccinated at 6 weeks of age, but they will require another injection at 10 weeks to provide them with full protection for the first year.
It is not recommended that vaccinations for VHD and myxomatosis are given at the same time. An interval of at least 2 weeks should be allowed between the injections.
The vaccination is given by injection usually into the scruff at the back of the neck. With the myxomatosis vaccine, your vet will administer about one-tenth of the volume of the injection into the skin which will produce a small lump that will disappear. The remainder is administered underneath the skin. This procedure will ensure your rabbit has full protection.
Occasionally a rabbit may not be fully protected against a condition, even after vaccination. This may be because the rabbit was already ill or was stressed when it was vaccinated and its immune system wasn’t working properly. Your vet will examine your rabbit before vaccination and if any signs of illness are detected will delay vaccination until your rabbit is well again.
There have been a small number of cases reported of rabbits vaccinated against myxomatosis contracting the disease. These rabbits exhibited symptoms of a very mild form of the disease and all recovered. In these cases, the vaccine may have protected them from the severe form of the disease.
Sometimes your rabbit may seem ‘off colour’ for a day or two after its vaccination and the injection site may also become tender and swollen. If these effects do not wear off it is worth taking your rabbit back to see your vet. If you are concerned about any symptoms in your rabbit do not hesitate to contact your vet for reassurance or advice.