Key takeaways

  • Myxomatosis is a contagious disease that can occur in both domestic and wild rabbits. Though it isn’t dangerous for some wild rabbit species, it’s often fatal in others.
  • Symptoms can include discharge from the eyes and nose, skin lumps, and purple skin spots.
  • There isn’t an effective treatment for myxomatosis, so it’s important to isolate rabbits who have the disease and protect healthy rabbits from potential exposure.

If you have a pet rabbit, you can help reduce their risk of contracting myxomatosis by keeping them inside or completely enclosing any outdoor space they have access to.

Myxomatosis can cause a variety of symptoms, including:

  • eye and nose discharge
  • reddened eyes and eyelids
  • drooping ears
  • skin lumps or purple skin spots
  • fever
  • lethargy
  • reduced appetite
  • weight loss
  • difficulty breathing
  • swelling of the:
    • ears
    • eyelids
    • lips
    • nose
    • anal or genital region
  • convulsions
  • coma
  • death

It’s important to note that not all rabbits experience severe symptoms. Some rabbits may even be asymptomatic, but could still die from the disease.

In the United States, the most common strain of the virus is almost always fatal in domestic rabbits. On average, death tends to occur around 6 to 9 days after infection.

The myxoma virus causes myxomatosis. It spreads through:

  • bites from blood-sucking insects, like mosquitoes and fleas
  • direct contact with a rabbit who has the virus
  • contact with materials, like food or bedding, contaminated with the virus

There are many different strains of the myxoma virus, some of which are more deadly than others.

Risk factors

Certain rabbit species have a higher risk of contracting severe myxomatosis and dying.

The virus naturally occurs in wild rabbits like cottontails and jackrabbits, and these rabbits are often very resistant to it. However, wild European rabbits and domestic rabbits are susceptible and have adverse outcomes.

Location can also be a risk factor. Most cases of myxomatosis in the United States occur on the West Coast, so rabbits living in other regions may not be as likely to contract the virus.

And any rabbit that spends time outdoors has a higher risk of contracting the virus from insects or contact with other rabbits.

To determine whether a rabbit has myxomatosis, a veterinarian will evaluate the rabbit’s symptoms and perform certain tests. They may take biopsies (small tissue samples) or swabs of nasal or eye discharge and send them off for polymerase chain reaction (PCR) tests, which can detect viruses like the myxoma virus.

There isn’t an effective treatment for myxomatosis, and vets often recommend euthanasia.

In some cases, a vet may offer supportive treatment, like pain relievers and intravenous (IV) fluids. Secondary bacterial infections are common and may require additional treatments, like antibiotics.

The vet will monitor the rabbit to see how the rabbit responds to supportive measures.

Myxomatosis is often deadly. The predominant strain of the myxoma virus in the United States is almost 100% fatal, and no vaccine is available.

Rabbits that contract other strains of the virus may have better outcomes. If your rabbit shows any symptoms, it’s important to isolate them from other rabbits and get them to a veterinarian as soon as possible.

One of the best ways to prevent pet rabbits from contracting the myxoma virus is to keep them indoors, where they can’t come into contact with rabbits or insects like mosquitoes that carry the virus.

A small 2024 study evaluated 11 rabbits with the myxoma virus and found that all of them had spent time outside.

If your rabbit spends time outdoors, you can help keep them safe by completely enclosing their outdoor space with mosquito screens. It can also help to keep wild rabbits out of your yard by installing a tall fence that goes several inches into the ground, so the rabbits can’t jump over the fence or dig under it.

Mosquitoes can also come indoors, so it can also help to keep your doors and windows closed as much as possible to keep them outside.

Keep this in mind

There is currently no vaccine for myxomatosis available in the United States, so prevention through these other methods is essential. If you’re concerned about myxomatosis, talk with your vet to make sure you’re doing all you can to lower your rabbit’s risk of contracting the virus.

Myxomatosis is a viral disease that can spread in domestic and wild rabbits. Though most cases in the United States are limited to the West Coast, these cases are almost always fatal.

Because there is no effective treatment for myxomatosis and no vaccine is available in the United States, prevention is essential. Keep pet rabbits indoors as much as possible, and if they spend time outdoors, completely enclose their space with mosquito screens and consider installing fences to keep wild rabbits away.