Myxomatosis In Rabbits

Myxomatosis In Rabbits: And the importance of the Flea

What is Myxomatosis?

Myxomatosis is a virus which causes illness in rabbits. It is from the Pox family of viruses and is very small, so small it can only be seen by using an electron microscope.

It was first discovered in the 1930’s in Brazil where the indigenous rabbit species the “Cotton tailed Rabbit” (Sylvilagus) was affected by minor disease signs which where usually self limiting.

It was then used in Australia in the 1950’s to control the massive rabbit population which were not indigenous to Australia and causing a lot of damage. To these rabbits which had no natural immunity to the virus it was devastating and cause a marked reduction in there numbers.

What are the signs of Myxomatosis?

Initially the virus causes swelling around the eyes. They may develop an ocular and/or nasal discharge. They may also develop other fluid swellings around the head, face,lips and inside the ears. They may also develop puffy swelling around the anus and genitailia. The swelling around the eyes may cause the rabbit to become blind and will have trouble eating as they may have distortion to the face and won’t be able to visualise food. Because they aren’t eating properly they become lethargic and weak. For wild rabbits this can be a death sentence as they will be easier to catch by foxes and other predators. They may even get lost or not be able to get away from vehicles on roads.

Following the initial signs the rabbit may develop secondary respiratory infection which is the main cause of death.

The length of time from infection to signs of disease can vary from five to fourteen days. Death can come as quick as twelve days in animals that are very susceptible to the virus but some animals may survive weeks and even months.

How can Myxomatosis spread?

Rabbit’s can contact myxomatosis from biting insects which includes fleas and mosquitoes. Rabbit fleas are the major route of transmission in Ireland. On mainland Europe the mosquito is a major vector.

When the flea bites an infected rabbit to suck it’s blood it also ingests the virus. The virus can live happily in the flea for a few months and even over winter in the flea. This means the next time the flea bites a susceptible rabbit it will become infected. Once the flea has bitten it’s new host the virus travels to a local lymph node and then into the bloodstream from there it can go to the sites where it mainly multiples; the eyes, nose, face, the soft skin inside the ears and even the anus and genitalia of the rabbit. Direct rabbit to rabbit transmission is nearly impossible without the flea.

Do all infected Rabbits die from getting infected with myxomatosis?

All breeds of rabbit are susceptible from your European wild rabbit to dwarf lops. But not all rabbits die. European wild rabbits have a recovery rate of approximately 10%. Recovery in pets is more likely and this would be with the help of intensive nursing care. This would include making sure they get enough to eat and drink. Also they will need medication to treat pneumonia.

It can be a very slow disease for them to recover from if they do and they are often left with facial and bodily scarring and scabbing.

What can I do to prevent Myxomatosis in my pet Rabbit?

  1. Vaccination
  2. Controlling biting insects

This will include keeping your pet rabbit away from wild rabbits so they do not pick up fleas from them. Cats can also carry rabbit fleas especially if they hunt a lot. Other methods include anti-flea treatments, sprays, spot-ons and insect strips (don’t forget the potential spread from mosquitoes).