Rabbit Hemorrhagic Disease (RHD):
Rabbit Viral Hemorrhagic Disease (RHD or VHD) is a highly contagious disease caused by a calicivirus that affects only rabbits of the Oryctolagus cuniculus species.
This includes wild and domesticated European rabbits, from which our own domesticated rabbits are descended.
RHD recently has been detected in carcasses of some North American native rabbits or hares, such as cottontails and jackrabbits.
It is also known by several acronyms: RHD (Rabbit Hemorrhagic Disease), RCV (Rabbit Calicivirus), and RCD (Rabbit Calicivirus Disease).
**1/10/2021 - RHDV2 has appeared on the east coast (Florida). Be aware and please consider preventive measures (below)**
Etiology & Ecology Quick Summary
Disease names: Rabbit hemorrhagic disease, rabbit viral sudden death, X-disease of rabbits,
hemorrhagic septicemia syndrome in rabbits, viral hemorrhagic pneumonia in rabbits,
rabbit viral hemorrhagic disease.
Mortality & Morbidity: Very high, between 50 and 100%, with the latter number probably being closer to actual mortality rates. Rabbits who survive this disease are carriers and shed the virus for at least 42 days, perhaps longer.
Susceptible Species: Domestic and wild European rabbits (Oryctolagus cuniculus), also called common rabbits.
Zoonotic Potential: Not a threat to public health at this time.
Transmission: Infected rabbits shed the virus in excretions and secretions. RHD is readily spread by direct contact, fomites, mechanical vectors, pelts, and infected rabbit meat and carcasses.
Persistence in the Environment: Highly stable, especially when ensconced in organic material.
Animal Products and By-Products: RHD is extremely hardy in rabbit meat; it may survive in chilled, frozen, or decomposing meat for months.
Cure: There is no known cure for RHD.
Symptoms:
- Loss of appetite
- Lethargy
- High fever
- Spasms
- Sudden death
- RHD is often a very swift and sudden killer, giving little warning.
- Rabbits may die without showing any symptoms at all. Some bleeding from the nose, mouth and rectum is sometimes seen.
- Any sudden rabbit death is suspicious and should be reported to your veterinarian or the State Veterinarian as a possible case of RHD.
Incubation period: Very short, and rabbits may die within 48 hours of exposure to the virus that causes RHD, but can be up to 10 days.
Vaccinations:
Vaccinations are available in countries where the disease in endemic, but there is no vaccine currently available in the US. Canadian vets and Washington state vets near the northern border have successfully worked with their respective regulatory agencies and have imported European vaccine for rabbit vaccination clinics.
How RHD Is Spread:
RHD is highly contagious. It can be spread by:
- Contact of a rabbit with inanimate objects contaminated by the virus (i.e. fomites). These objects would include rabbit food, bedding, or water; human clothing, shoes, and car and truck tires.
- Direct contact of a rabbit with an infected rabbit through oral, conjunctival, or nasal routes; contact with the feces of an infected rabbit.
- Contact with rabbit products such as fur, meat or wool from infected rabbits.
- Insects, birds, fleas, mosquitoes, flies, and animals such as rodents are known to spread the virus by acting as indirect hosts. They can transport the disease, for example, from an infected rabbit to an unaffected rabbit.
- Humans can spread the virus to their rabbits if they have been in contact with infected rabbits or in contact with objects contaminated by the virus, including feces from an infected rabbit.
How to Protect Your Rabbits
- House your rabbits indoors. We strongly recommend that rabbits be kept indoors, or in enclosed environments. Rabbits who live or exercise outdoors are more at risk for contracting this disease.
- Wash your hands thoroughly before handling your rabbits, particularly when you come home from places where other rabbits may have been, or where people who have been in contact with rabbits may have been. This would include places such as feed stores, pet stores, fair grounds, humane societies, etc.
- Change your clothes and wash your hands after handling or coming in contact with other rabbits. Wash these clothes twice in hot water before you wear them around your rabbit.
- If you volunteer at a shelter in an area with an outbreak, have some special clothes and shoes that you wear only at the shelter. You may want to wear shoe covers or plastic bags over your shoes, secured with a rubber band. When you leave the shelter, remove the bags and dispose of them before you get into your car, making sure not to touch the outside of the bag. Follow clothes laundering instructions above, and shoe disinfecting instructions below. This protects the shelter rabbits as well as your own. The same considerations apply to anyone who sees rabbits at work and also has rabbits at home.
- Adopt a “no shoes in the house” policy, or keep your bunnies from running in high traffic areas of your home.
- To disinfect shoes that may have been contaminated, place the shoes in a foot bath that contains one of the below disinfectants. The shoes must be in contact with the disinfectant for at least ten minutes, during which time the disinfectant must remain wet. Merely spraying shoes with disinfectant and leaving them to dry is not effective.
- Use an effective disinfectant for this virus:
- bleach (1:10 dilution)
- potassium peroxymonosulfate (Virkon)
- accelerated hydrogen peroxide (Prevail, Accel, Rescue wipes or solution, and Peroxigard)
- 2% 1-Stroke disinfectant
- Parvosol
- parvoviricide disinfectant
- You may wish to speak with your veterinarian about how to obtain these.
- Disinfect objects using one of the disinfectants above. Remember it must stay in contact with the item and remain wet for at least ten minutes.
- Know your sources of hay and feed and if they are near areas of any outbreaks
- Minimize insects in your home by installing window and door screens. Eliminate mosquitoes and flies from your home.
- Quarantine any new rabbit for at least 10 days. Always handle quarantined rabbits last, and keep all supplies for them separate from your other rabbit’s supplies.
Educating yourself and others about RHD is one of the best ways to help protect your rabbits. Don’t panic, but get involved on spreading the word to others in the rabbit community.
Most Important: Protect all Rabbits from RHD
Unexplained and suspicious rabbit deaths, especially when they occur in clusters of several rabbits dying in a short period of time, should be reported to your local veterinarian. All veterinarians are being instructed to report any suspicious deaths to the State Veterinarian. This is very important to prevent the spread of this awful disease.
If you suspect that you have a possible case of RHD, do not bury the body or take it out of the house, but call your vet to learn the proper handling procedures. To conceal an infected rabbit or knowledge of a RHD infection is to sentence may other rabbits to death.
REMEMBER – DON’T PANIC, but do educate yourselves and others.
Timeline of recent events:
- December 2020 - RHDV2 appears on the east coast (Lake County, FL). RHDV2 confirmed in meat-type domestic rabbits (Oryctolagus cuniculus) on one non-commercial premises in Lake County, Florida. This is the first detection of RHDV2 in domestic rabbits from Florida. Clinical signs included bleeding from the nose and sudden death. The affected premises has been quarantined. Florida State Animal Health Officials and the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Services (APHIS) have begun an epidemiological investigation into the outbreak. 18/18 rabbits dead - 100% mortality rate.
- March & April 2020 New Mexico – Domestic rabbits confirmed to have died of RHDV2 have been found in Lincoln, Curry, Doña Ana, Chavez, McKinley, Cibola, Torrance and Eddy Counties. Tests of dead wild jackrabbits and cottontails in southern & eastern NM also confirmed RHDV2.
- 3/3/2020 Manhattan, New York City (NY) – 11 rabbits in a vet hospital died, tested positive for RHDV2.
- 1/6/2020 Clallam County, WA – 3 dead rabbits tested positive.
- 11/7/2019 Whidbey Island, WA – a domestic stray rabbit tested positive, and the Washington State Dept of Agriculture issued a quarantine on rabbits entering/leaving Whidbey Island.
- 9/23/2019 San Juan Island, WA (San Juan Islands) – 2 domestic rabbits that had direct contact with stray/feral rabbits died from RHD.
- 9/23/2019 Saanich (Vancouver Island), BC – Canada – two stray/feral rabbits died, confirmed RHDV.
- 7/9/2019 Orcas Island, WA (San Juan Islands) – A pet rabbit died from RHDV2. No other rabbits are on the property.
- 6/21/2019 Vancouver, BC – Canada – Several pet rabbits in a downtown Vancouver apartment died from RHD.
- 4/10/2019 Vancouver Area, BC – Canada – Four stray domestic rabbits in Parksville died from RHDV2.
- 12/7/2018 Clover Township, PA – 40 pet rabbits in a barn died, confirmed by the USDA to have died of RHDV1. This type 1 virus is a different strain than the 2018 type 2 cases in Ohio and Canada.
- 9/19/2018 Medina County, OH – Four rabbits on a single property died and tested positive for RHDV2.
- 3/2/2018 Vancouver Area, BC – Canada – An outbreak of Rabbit Hemorrhagic Disease (RHDV2) was reported starting in February in the Nanaimo area on Vancouver Island in British Columbia, Canada, with cases on the Canadian mainland in the Vancouver, BC area. Canadian vets worked together and imported a European vaccine. According to the Ministry of Agriculture, no new RHDV2 cases were reported from May 2018 – March 2019.
Educate yourselves further:
- https://www.facebook.com/groups/rabbithemorrhagicdiseasenewsnetworkcanada/ (an up to date FB group for rabbit owners in the US concerned about RHDV2 – we highly suggest you join!)
- https://www.aphis.usda.gov/animal_health/emergency_management/downloads/sop/sop_rhd_e-e.pdf (the USDA guidelines and information)
- https://www.oie.int/fileadmin/Home/eng/Animal_Health_in_the_World/docs/pdf/Disease_cards/RHD.pdf (a great fact sheet)
- https://cms.agr.wa.gov/getmedia/07915d2d-bfd5-4cbb-b443-ab3b42b72722/RHDFactsheet (fact sheet from Washington State Dept of Agriculture)
- https://thebritishrabbitcouncil.org/What%20should%20I%20do%20if%20I%20suspect%20a%20possible%20VHD%20outbreak.pdf (a guide for rabbit owners that suspect an outbreak in their home)
- https://wsvma.org/2020/02/14/qa-about-the-rabbit-hemorrhagic-disease-vaccine/ (all about the vaccine in development)
- https://www.krqe.com/news/new-mexico/disease-blamed-for-wild-rabbit-deaths/?fbclid=IwAR3VSv7uhIFD6lDqk88VkQdpWYN0ypIp8nfdBywtUgl8Nd_FuAVwjLs8tOU (news release with video regarding wild rabbit cases in NM)
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