The Colorado State Veterinarian’s Office distributed this communication to Colorado veterinarians on April 20, 2020.
The Colorado Department of Agriculture (CDA) in conjunction with Colorado Parks and Wildlife (CPW) has confirmed a case of Rabbit Hemorrhagic Disease Virus Serotype 2 (RHDV2) in wild cottontail rabbits in Costilla County. This is the first confirmed case of RHDV2 in Colorado.
On April 15th, CPW was notified of a report in Costilla County of several wild cottontails found dead. Three cottontail rabbits were collected and samples from these rabbits were sent to the Foreign Animal Disease Diagnostic Laboratory at Plum Island. On April 17th, the laboratory confirmed that these rabbits had RHDV2.
RHDV2 has recently been confirmed in domestic and wild rabbits in Arizona, New Mexico, and Texas. The presence of RHDV2 in the U.S. domestic rabbit industry and in the wild rabbit populations could potentially impact the pet rabbit industry; 4- H, FFA, and other hobby groups; exhibitions; laboratories; and the meat, pelt, and hunting sectors.
RHDV2 is not infectious to people or domestic animals other than rabbits. However, multiple dead or sick rabbits can also be a sign of tularemia or plague, diseases that can cause serious illness in people. Do not handle or consume sick or dead wildlife, and do not allow pets to contact or consume wildlife carcasses.
Please be aware that the virus causing rabbit hemorrhagic disease (a calicivirus) is NOT in any way related to the circulating novel coronavirus that primarily affects people.
RHDV2 Background:
Rabbit Hemorrhagic Disease Virus Serotype 2 is a highly contagious and fatal disease of domestic rabbits and wild rabbits. This is a foreign animal disease (FAD) and is of high concern at the state and federal levels. The recent involvement of wild cottontails and hares is of particular concern.
Clinical signs: Often the only signs of the disease are sudden death and possibly blood stained noses caused by internal bleeding. Infected rabbits may also develop a fever, be hesitant to eat, or show respiratory or nervous signs. Many of the rabbits confirmed with RHDV2 recently in Arizona and New Mexico have shown no clinical signs or gross pathology other than sudden death.
Transmission: RHDV2 can be spread through contact with infected rabbits, their meat or their fur, or materials coming in contact with them. Scavengers and birds may play an important role in indirect transmission of the RHD virus.
Prevention: A vaccine for RHDV2 is not currently available in Colorado. Rabbit owners should practice good biosecurity measures to protect their animals from this disease, such as washing your hands before and after working with rabbits and not sharing equipment with other owners. Rabbit owners should also avoid contact with wild or feral rabbits.
Reporting of rabbit illnesses or deaths in Colorado:
Owners: Rabbit owners who have questions about the disease should contact their veterinarian.
Veterinarians: Veterinarians must report suspected RHDV2 cases in domestic rabbits to the State Veterinarian’s Office at 303-869-9130. Disease investigations will be completed by a Foreign Animal Disease Diagnostician.
Wildlife: To report suspect cases (sick or dead wild rabbits, hares, or pika), contact your local Colorado Parks and Wildlife office.
For additional information on RHDV2, please visit the CDA Rabbit Hemorrhagic Disease webpage.