By Dr. Laurie Hess | Director of Pet Health and Nutrition at ZuPreem
What is it?
If you own a pet rabbit, you have likely heard about a new virus that is killing both pet and wild rabbits around the world by causing uncontrollable bleeding. RHD, also called viral hemorrhagic disease, is a virus that is endemic to Australia, New Zealand, Cuba, Europe, and parts of Asia and Africa. In the past few years, cases have occurred in Canada and in the U.S. in Ohio, Washington, New Mexico, Texas, Colorado, Arizona, Nevada, and New York City. Caused by two viruses in the calicivirus family, RHD can affect both wild and domestic (pet) rabbits and has been spreading, in part, due to its presence in wild rabbit populations.
How would I know if my rabbit has it?
The incubation period for RHD is 1-5 days after exposure. All ages of rabbits are susceptible. RHD causes liver inflammation (hepatitis) and subsequent inhibition of blood clotting, as the proteins needed for normal clotting are made in the liver. Affected rabbits may die suddenly without any outward signs, or they may have fever, decreased appetite, lethargy, muscle spasms, difficulty breathing, blue-tinged lips (from lack of oxygen), and obvious bleeding from anywhere on their bodies (mouth, eyes, rectum, vagina, skin, etc.). Death occurs due to internal bleeding, and typically 80-100% of affected rabbits die. Those that survive develop antibodies to the virus and are resistant to reinfection for an unknown amount of time. They can carry the virus and shed it into their feces and respiratory tract secretions, potentially infecting other rabbits, for up to 2 months. This disease is not believed to be transmittable to people or to other household pets.
How is it spread?
Spread of the virus occurs through inhalation, ingestion, or absorption (through cuts in skin) of contaminated material. The virus persists in the environment for months and can be spread through direct contact with infected rabbits or with contaminated objects (cages, feeders, grooming equipment, bedding, clothing, food, water, etc.). While most rabbits that are exposed to infected rabbits or contaminated objects develop infection, a small number of exposed rabbits will not.
How can I help prevent my rabbit from getting it?
Try to keep your rabbit away from wild rabbits. That means not taking your pet outside. If your rabbit is normally housed outside, keep its hutch off the ground. Don’t let your pet graze outside. Don’t exposure your rabbit to other pet rabbits unless absolutely necessary. Take your shoes off when you come inside, and clean them with dilute bleach, particularly if you have been out in areas where wild rabbits may have traveled. If you handle other peoples’ rabbits, be sure to wash thoroughly, and change your clothes before you touch your rabbit. Try to limit handling of your rabbit by other rabbit owners, and avoid going to rabbit shows/fairs/meetings. Try to control spread of the virus by insects, rodents, or other animals that could carry it into your home or your rabbit’s hutch. Try not to travel with your rabbit, and if you do have to travel, be aware of whether RHD has been reported at your destination. If you suspect your rabbit has been exposed to an infected rabbit or contaminated items from an infected rabbit, contact your veterinarian, and disinfect appropriately. RHD is inactivated by a 10% solution of bleach and water. Disinfectants such as Lysol, Clorox wipes, and Odoban containing quaternary ammonium compounds as the disinfectant are not effective in killing RHD. If you see a dead wild rabbit, do not touch it; instead contact your local animal control officer so that they can collect the remains for appropriate laboratory testing.
Is there a vaccine available to prevent RHD infection?
Currently, there is no licensed vaccine to prevent RHD available in the U.S. In cases of emergency outbreak, where there is a confirmed case of RHD, veterinarians can contact their state veterinarian to apply for a conditional license to import the vaccine.
For more information, see https://www.aphis.usda.gov/publications/animal_health/fs-rhdv2.pdf