Have you ever wandered what a group of rabbits were called? A group of bunnies is called a fluffle, yes you read that right. The ever-appropriate name is used to refer to wild rabbits which can also be called a colony – but why would you? Stick with fluffle.
While we are talking about bunnies, both wild and domesticated, we have a new threat to them! In Pennsylvania a disease is spreading amongst wild and pet rabbits, its call Rabbit Hemorrhagic Disease. In the next few paragraphs we will help educate everyone on how to keep this disease at bay.
What is RHD?
RHD is a foreign animal disease, meaning it is not typically found in the United States and is of high concern to domestic and wild animal health. RHDV2 is one of two viruses that can cause RHD; it is a highly pathogenic and contagious calicivirus affecting hares, rabbits, and closely related species. RHDV2 was first identified in domestic rabbits in France in 2010 and since then, it has been responsible for mass die-offs in wild hare and rabbit populations in several countries including the United States.
How does RHDV2 spread?
The virus is extremely hardy and highly contagious. It can spread between hares and rabbits via many pathways that include direct contact with an infected live or dead individual; ingestion of contaminated food or water; inhalation; contact with contaminated equipment, tools, and enclosures; viral movement by flies, birds, biting insects, predators, scavengers, and humans; and contact with urine, feces, and respiratory discharges from infected individuals. The virus can survive on clothing, shoes, plant material, or other items that could accidentally be moved from an infected area.
How does RHD affect hares and rabbits and what can we look for?
There is no specific treatment for the disease, and it is often fatal (generally 75%-100%) with the potential to result in large, localized mortality events. Hares or rabbits that do not immediately die following infection may present with poor appetites, lethargy, and blood coming from their mouths or noses.
Is RHD a public health concern?
RHD is not infectious to people or domestic animals other than hares or rabbits. However, multiple dead or sick hares or rabbits can also be a sign of tularemia or plague, diseases that can cause serious illness in people. Therefore, it is important that the public does not handle or consume wildlife that is sick or has died from unknown causes. It is also important to prevent pets from contacting or consuming wildlife carcasses.
Where exactly has RHDV2 been detected in wild hares and rabbits?
The United States Department of Agriculture’s Animal and Plant Health Inspection Service maintains an up-to-date map at the following URL: https://www.aphis.usda.gov/aphis/maps/animal-health/rhd
Currently this disease is in the western USA, but small cases of domesticated rabbits in Tennessee and Georgia.
Early detection and removal of suspect carcasses will be Pennsylvania’s best defense to mitigate any RHD outbreaks. We encourage members of the public to report any lagomorph mortality events (two or more dead hares or rabbits at the same location) to their local Game Commission office for further investigation. The public should avoid touching any dead hares or rabbits.
Once established, RHD can quickly spread amongst wild rabbit and hare populations. Currently, Pennsylvania is significantly isolated from affected wild populations. Therefore, the main risk of the disease being introduced to the Commonwealth is through the importation of infected rabbits or hares, their products, or contaminated materials.
RHD is also a threat to domestic rabbits but the Game Commission is not involved with domestic animals. PA Department of Agriculture is responsible for domestic rabbits within the Commonwealth to the extent of inspecting rabbit slaughter facilities. Such breeding and processing facilities may voluntarily consent to USDA and/or FDA oversight but such oversight is not required. In addition to PA Department of Agriculture, USDA, and FDA, private veterinary practices can also provide animal health expertise for domestic/pet rabbits. Any questions regarding disease surveillance in domestic rabbit or hare species should be directed to those other entities.
Veterinary diagnostic laboratories are aware of RHD and any detections of RHDV2 in domestic lagomorphs in PA will be reported to the Game Commission.
Clean and disinfect (after thoroughly cleaning, disinfect with a 1:10 solution of household bleach to water, soaking for at least 10 minutes) all surfaces and equipment that may have contacted suspected RHD-positive hares or rabbits. These precautions are incredibly important as the disease can be easily transmitted amongst and between wild and domestic populations.
If instructed to dispose of carcasses, either incinerate or bury them deep enough to prevent scavenging (> 3 ft). Carcasses can also be disposed of in the commercial trash. When handling any carcass, always wear gloves and double bag the carcass.
The virus is resilient and may remain on the landscape for weeks or months.