In July 2010, 3 fatal cases of myxomatosis
(mix-oh-ma-tow-sis) in rabbits were reported in two
homes in a neighborhood in the San Gabriel Valley. The
rabbits died in the last two weeks of June. The pet
rabbits lived mostly indoors but had access to the
outdoors, where they could have been bitten by
mosquitoes, fleas, or black flies. One case was
confirmed after death by biopsy of swollen skin. All
three rabbits showed typical symptoms (see description
below). Blood tests on two rabbits showed low white
blood cell counts, and increased liver enzyme and kidney
What is myxomatosis?
Myxomatosis is disease of rabbits caused by a virus. The
onset of illness is rapid and death may occur within
days or hours. Symptoms can include fever, loss of
appetite, and swelling of the nose, eyelids, lips, ears,
or genital area. Sudden death may occur.
Myxomatosis is found naturally in wild rabbits in
California, especially along the coast. Wild rabbits are
generally more resistant to the effects of the virus,
but may become infected and spread the disease. In 1950,
this virus was deliberately introduced into Australia in
an attempt to rid the area of wild rabbits. Initially,
90% of infected rabbits died, but over several years,
the mortality rate dropped to approximately 25%.
How is myxomatosis spread?
This virus can be spread from infected rabbits to other
rabbits by the bites of any bloodsucking insect,
including mosquitoes, fleas, black flies, and ticks. It may also spread
through direct contact between rabbits or contact with
surfaces contaminated by an infected rabbit.
Can people or other animals catch myxomatosis?
No. Myxomatosis causes illness only in rabbits.
How can I protect my rabbits from myxomatosis?
1. Protect your rabbits from fleas, mosquitoes, and
small biting flies. Some products used to kill or
repel insects are toxic to rabbits. Make sure you
use only products that are safe for rabbits. It is best
to keep your rabbit indoors. If you have to let
your rabbit outdoors, make sure it is protected from
insect bites by screens or netting that keeps out all
insects. Contact your veterinarian on how to best
protect your rabbit.
2. Stop mosquito breeding on your property. Check
your property for stagnant water twice weekly (examples:
drainage systems, flowerpots, old tires, gutters) and
remove any that you find.
3. Isolate sick rabbits. if you have a sick
rabbit, keep it in an area away from other rabbits. Wash
your hands before and after handling the sick rabbit. Do
not share rabbit equipment (bowls, cages, toys) until
after you thoroughly clean and disinfect it.
4.Quarantine new rabbits. If you bring any new
rabbits into your home, keep them in a cage far from
your other rabbits, and use separate food and water
bowls. Wash your hands well before and after handling
the new rabbit.
5. Contact your veterinarian if you see any
symptoms of myxomatosis in your rabbits.
6. Report myxotmatosis cases in Los Angeles
County to Veterinary Public Health (213) 989-7060 or
complete and fax in
version of alert
to rabbit owners from Western University College of