Myxomatosis
History
The Myxomatosis virus originates from South America where it causes a mild disease in the wild rabbit population. European rabbits had been introduced to Australia by early colonists but by the 1950’s the rabbit population was out of control as they had no natural enemy. In an attempt to reduce rabbit numbers the Myxomatosis virus was intentionally introduced to Australia. By accident the virus was also introduced into Europe killing off the wild rabbit population.
How is it spread?
The virus is spread by direct or indirect contact but most often by parasites. The rabbit flea, mosquito and flies are the most important methods of spreading the virus. The virus can survive for several months in over wintering rabbit fleas and mosquitoes. If your rabbit has an infected eye or abscess on its body or impacted faeces on their bottom, they are at risk. A fly may land on a dead or dying wild rabbit infected with the virus and then land on your domestic rabbit if it has one of the above ailments to attract it.
Symptoms
- Swelling of the genitals and of the head, especially the eyelids which results in blindness.
- The rabbit’s appetite remains normal until shortly before death which is on average 13 days after infection. You may have seen wild rabbits in late summer just sitting on the side of the road in country areas. A heart-breaking sight as they literally starve to death as their mouths and lips swell so much and they cannot see or smell their food.
- There are other forms of the disease that result in respiratory symptoms that can be very difficult to differentiate from other causes of pneumonia such as Pasteurellosis.
- Not all affected rabbits die - although in the wild, fewer than 10% survive. But even with intensive nursing, Myxomatosis can be a very serious disease, leading to severe scabbing and scarring on the head and body
Treatment and Prevention
Rabbits affected with the acute form of the disease cannot be treated. To prevent suffering, euthanasia is the only option.
There is a chronic form of the virus if the rabbit has built up some immunity. They end up with lumps on their head, ears and paws which form scabs and they have a 50% chance of survival once the lesions shrink. Good home nursing and antibiotics are needed.
To control the spread of the disease it is important to:
-
Disinfect hutches but make sure that the disinfectant used is not harmful to rabbits. Good hygiene will keep flies away, so clean hutches regularly.
-
Flea control in the form of spot-on will control rabbit fleas and mosquitoes. Advantage can be used in rabbits and there is a very new product for use in rabbits and small pets.
-
If you are in an area near a lake or pond, then mosquito control is more important and you may even have to use a mosquito net over the hutch during hot summer evenings. Dry bedding will also discourage mosquitoes.
Vaccination is the best form of control. We most commonly use Nobivac vaccine which can be given to rabbits as young as 6 weeks and it produces an immunity 2 weeks after vaccination. An annual vaccination is given and the best time to give it is in May or June.
Rabbits may occasionally develop a lump after vaccination but this disappears over time. If there is a high risk of infection, we would make you aware and revaccination every 6 months is advisable. Vaccinations should not be given within 2 weeks of Viral Haemorrhagic Disease vaccinations.
