Myxomatosis & Rabbits

Myxomatosis is a viral disease of rabbits endemic to the west coast of the US, meaning it is always a threat to domestic and wild rabbits and has been for many years.

This poxvirus known as the Myxoma virus is spread through bites from vectors like fleas, mosquitoes, ticks and mites, but it can also be spread by fomites or through animal to animal contact. A fomite is an object such as bedding, clothing, feed, housing, etc. that has contacted an infected rabbit and is then in contact with a healthy rabbit. Some rabbit species, such as European rabbits, are highly susceptible to this disease and it can cause a high mortality. This disease does not affect humans.

Myxomatosis occurs most often during warm months due to increased vector activity.

When to Suspect Myxomatosis

Myxomatosis should be suspected in rabbits that have access to the outdoors and exhibit swelling around the eyes and/or genitals or show signs of skin nodules, high fever, lethargy and poor appetite. There is no cure and treatment is rarely successful. The infection eventually leads to depression, pneumonia and death. Myxomatosis should also be suspected when a rabbit with access to the outdoors dies unexpectedly and there is no explanation. These rabbits may have only had a respiratory infection without skin lesions and will appear to have died suddenly. 

What to Do if You Suspect Myxomatosis

If you suspect your rabbit(s) is/are infected or have died from a Myxomatosis infection, you should report this incident to the Oregon Department of Agriculture’s (ODA) Animal Health Hotline at (503) 986-4711. Keep the deceased rabbit in a cool dry place protected from predators. ODA will contact you to get additional information and decide if testing is warranted.

Treatment and Prevention for Myxomatosis

Unfortunately, there is no treatment for Myxomatosis, so prevention is most important.  Vector control is the best prevention for rabbits that venture outside. Talk to your veterinarian about parasiticide options and consider creating outdoor spaces that are protected by mosquito netting. Veterinarians recommend that domestic rabbits be kept indoors with screened windows and doors to prevent access to mosquitoes.Also, have an isolation area away from your healthy rabbits to keep sick rabbits until they can be tested or recover.