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Urgent Health alert - Myxo epidemic

From: Hilary Stern [] 9-8-2019

Hello rabbit owners,


I wanted to let you know that we are having a severe myxomatosis epidemic this year. Myxomatosis is a viral disease spread by biting insects, particularly mosquitoes, and due to the late spring rains we are having a bumper crop of western tree hole mosquitoes this year.  As you probably guessed from the name these mosquitoes breed in trees, and therefore don't require ground water. Fleas, lice, and mites can also spread myxomatosis.


The California strain of the myxoma virus is extremely virulent, with a >99% fatality rate in domestic rabbits We have no vaccine against this disease in the U.S., and there is no effective treatment. The only defense then is to prevent exposure in the first place. Outdoor rabbits should be brought indoors immediately, and indoor rabbits should be kept indoors. Check your screens and make sure they have no holes, and keep unscreened doors and windows closed. If you are unable to bring your rabbits indoors cover their enclosures in mosquito netting.


I have seen six rabbits with myxomatosis in the past few weeks. Unlike in previous years when cases were sporadic and localized, these cases are coming from all over. So far I have seen cases from Bonny Doon, Santa Cruz, Ben Lomond, Boulder Creek, and Aptos. Other veterinarians have reported cases in Watsonville, Salinas, and Santa Clara county.


Symptoms of the disease are mild to marked swelling of the eyelids, base of the ears, and genitals. If they survive long enough rabbits go on to develop discharge from their eyes and the nose, and labored breathing.  Fever is present initially, but body temperature falls as the rabbit becomes more ill.


Myxomatosis is a reportable disease in California, so if you lose any rabbits to this disease please report it to Dr. Alyssa Louie at the California Department of Food and Agriculture <>. Please also report cases to the House Rabbit Society, they are keeping track of the outbreak on their webpage <>.


If you have local friends with pet rabbits please forward this email to them. More information is available at .


Feel free to contact me if you have any questions.


Thank you,


Hilary Stern, DVM

Practice limited to birds, reptiles, and small mammals

Animal Hospital of Soquel
2651 Soquel Avenue
Santa Cruz, CA 95062

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