Viral Hemorrhagic Disease (VHD)
Rabbit Viral Hemorrhagic Disease (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. It has not been known to affect any North American native rabbits or hares, such as cottontails, snowshoe hares and jackrabbits. VHD is also known by several other acronyms: RHD (Rabbit Hemorrhagic Disease), RCV (Rabbit Calicivirus), and RCD (Rabbit Calicivirus Disease). VHD was first seen in China in 1984, and has since spread to Mexico, Continental Europe, Israel, the UK, Australia and New Zealand.
Symptoms may include:
- Loss of appetite
- High fever
- Sudden death
VHD, however, 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 VHD
- The incubation period of this disease is very short, and rabbits may die within 48 hours of exposure to the virus that causes VHD.
- The death rate of rabbits exposed to this virus is 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.
- Rabbit calicivirus is a very hardy virus, remaining viable in the environment for 105 days at 68F (i.e. remains stable for 105 days at room temperature) and for 225 days at 39F. It resists freezing.
- There is no known cure for VHD. Vaccinations are available in countries where the disease in endemic, but there is no vaccine currently available in the US.
How VHD Is Spread
As was mentioned, VHD is highly contagious. It can be spread by:
- Contact of a rabbit with inanimate objects contaminated by the virus (i.e. via fomites). Such object would include clothing, shoes, and car and truck tires.
- Direct contact of a rabbit with an infected rabbit or the feces of an infected rabbit.
- Contact with rabbit products such as fur, meat or wool from infected rabbits.
- Insects, birds, 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 suggest that they 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 rabbits. Wash these clothes twice in hot water before you wear them around your rabbit.
If you volunteer at a shelter, have some special clothes and shoes that you wear only at the shelter. You may want to wear 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, you need to place the shoes in a foot bath that contains one of the following: 10% bleach solution, 2% 1-Stroke Disinfectant, Parvosol, or parvoviricide disinfectant. You may wish to speak with your veterinarian about how to obtain these. The shoes must be in contact with the disinfectant for at least ten minutes. The foot bath is recommended as it is important that during the ten minute disinfection time that the disinfectant remains wet. Merely spraying shoes with disinfectant and leaving them to dry is not effective.
- 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 5 days. Always handle quarantined rabbits last, and keep all supplies for them separate from your other rabbits supplies.
- To disinfect objects, use one of the disinfectants above, remembering that it must stay in contact with the item and remain wet for at least ten minutes.
What You Can Do
Educating yourself and others about VHD is one of the best ways to help protect your rabbits. Dont panic, but get involved on spreading the word to others in the rabbit community.
Take the time to read the information at the following recommended websites.
- The British House Rabbit Association website is at www.houserabbit.co.uk/index.htm. It has information of particular relevance to rabbit caretakers in the UK and Europe.
- The APHIS website is at http://www.aphis.usda.gov/animal_health/emergingissues/byspeciescategory/rabbit.shtml.
Informing veterinarians, shelters, pet stores that sell rabbits and fellow rabbit lovers about VHD is important to helping to protect all rabbits. Make copies of this article to show your local vets, etc., and refer them to above websites. The VHD in the US Coalition website has informational flyers that you can download and distribute as well. We need your help to spread the word!
Most Important: Protect all Rabbits from VHD
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 VHD, 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 VHD infection is to sentence may other rabbits to death as well.
What is the Government Doing?
Currently, the USDA and APHIS have no jurisdiction over rabbits. Individual State Veterinarians will be the ones to decide what protocol to follow in event of an outbreak; however, it is likely they will invite APHIS to participate with them to handle an outbreak. House Rabbit Society Chapter Managers and leaders of other house rabbit and rabbit rescue groups should also contact their State Veterinarians. The state authorities should know that there are concerned companion rabbit caregivers and rabbit rescues in your state whose interests must be included in policy making. We need to make sure our rabbit companions are not forgotten.
Remember, dont panic, but educate yourself and others. Together we can make a difference.
Important News Regarding Rabbit Viral Hemorrhagic Disease (VHD)
2/10: In February 2010, an outbreak of RHD/VHD was found at a home in Pine County, Minnesota, which supplies rabbits to a wildlife center to be used as food for predator animals. At this time, 25 domestic rabbits died of the disease. While this was only confirmed by USDA APHIS in April 2010, the outbreak appears to have been limited to that single location at that single time. It was originally thought that feed contamination was the source of the disease. To our knowledge there are no quarantines planned or anticipated. HRS recommends that rabbits continue to be cared for as we have always recommended: in the house.
6/12/05: Press release by Bureau of Animal Health, Indiana.
Rabbit Hemorraghic disease confirmed in Indiana. Investigation ongoing in Kentucky also.
6/7/05: VHD confirmed in Evansville, Indiana. This is the fourth US outbreak. There is not much published info on this current outbreak. There is a new yahoo list, VHDInfo, that appears to have current information on the outbreak. http://groups.yahoo.com/group/VHDInfo/ . We hope to have more info and links soon.
From the APHIS emergency update:
” On June 7, 2005, Rabbit Hemorrhagic Disease (RHD) was confirmed at a private residence in Vanderburgh county, Indiana by the Foreign Animal Disease Diagnostic Laboratory (FADDL) on Plum Island, NY. Specimens from these rabbits were positive for RHD antigen on ELISA, electron microscopy, and PCR. A FAD investigation was initiated on June 3, 2005 on a premises that raises rabbits primarily for sale to reptile owners as a food source for snakes. The investigation revealed that many of the 200 rabbits on the premises suddenly died during the past 10 days. Less than a dozen rabbits had recently been purchased from Kentucky and introduced into the herd. An e pidemiologic investigation has begun in Kentucky. The remaining rabbits are quarantined and will be euthanized and disposed of in accordance to State regulations. Cleaning and disinfection of the area will follow. The Indiana epidemiological investigation is ongoing.”
12/11/01 Update: VHD has again struck here in the USA. This is the third US Outbreak. This time it is not a rural location. An exotics animal facility in Flushings (Queens) NY that is open to the public is the site of the current outbreak.
8/17/01 Update: Second US Outbreak. On August 17, 2001, USDA’s Foreign Animal Disease Diagnostic Laboratory (FADDL) confirmed Viral hemorrhagic disease of rabbits (VHD) also known as rabbit calicivirus disease from a rabbitry in Utah county, Utah. A Mercer County, IL premises, which received 72 rabbits from the infected Utah premises was also involved. Preliminary test results are positive for the rabbits that were received from the infected Utah premises. Over 3,000 rabbits have been euthanized in conjunction with this current outbreak.
On April 10, 2000, the first confirmed cases of Rabbit Viral Hemorrhagic Disease in the United States were reported by the United States Department of Agriculture (USDA) through its Animal and Plant Health Inspections Service (APHIS). The affected rabbits lived on a farm in Crawford County, Iowa. Of the twenty-seven rabbits in the rabbitry, twenty-five died, with the remaining two being purchased and euthanized by the state. Up until this confirmed case, the US had been considered free of VHD.