Often fatal to domestic and wild rabbits, the disease has led to outbreaks in multiple US states since 2020.
A vaccine for rabbit hemorrhagic disease (RHDV2) has been granted a Conditional Use License by the United States Department of Agriculture's Center for Veterinary Biologics (USDA-CVB) to be further manufactured and distributed. The therapy is produced by Medgene, an animal health company in Brookings, South Dakota, that develops targeted platform vaccines.1
RHDV2 is highly contagious and has a high mortality rate. All domestic rabbits are at risk of infection. Clinical signs of the disease include fever and sudden death—within 12 to 36 hours after infection. Rabbits with RHDV2 that survive longer can develop depression, anorexia, respiratory distress, and reddening of the conjunctiva.2
"Conditional approval is a testament to the proven safety and efficacy of this important vaccine. Medgene stepped up at a critical time and the rabbit community is more than grateful for the protection and prevention of RHDV2 deaths in our beloved bunnies," said Anthony Pilny, DVM, DABVP (Avian) medical director for the House Rabbit Society; an owner and director of education for Arizona Exotic Animal Hospital, in a news release.1
RHDV2 is classified as a Foreign Animal Disease by the USDA-CVB, and it affects wild rabbits as well as domestic pets. In the US, an outbreak of RHDV2 at an exotic animal clinic in the Manhattan borough of New York, New York, led to the deaths of 11 rabbits. The disease has since spread throughout the US with outbreaks reported in New Mexico, Arizona, Texas, Colorado, Nevada, California, Utah and Mexico.1,2
The USDA-CVB granted Medgene's vaccine Emergency Use Authorization for the RHDV2 vaccine in 2021, after the therapy was successfully tested for reasonable expectation of safety and efficacy. Additional tests have continued to measure the vaccine's safety, efficacy and duration of immunity.1
"(RHDV2) has been heartbreaking for the rabbit community. When RHDV2 first hit, we were grateful to provide some hope against the onslaught of the disease under USDA-CVB's Emergency Use Authorization. Today, we're able to support it with a Conditional Use License. This success is a combined effort between USDA-CVB, state veterinarians, rabbit owners, and the Medgene team," said Gary Bosch, DVM, executive vice president of Medgene, in the release.1
Veterinary professionals can provide rabbit owners with more information on RHDV2 and the Medgene vaccine. The American Veterinary Medical Association (AVMA) suggests veterinarians speak with rabbit owners about appropriate disease control, which can include washing hands before and after handling rabbits, maximizing insect and rodent control, using pelleted feed from unaffected states, and not allowing domestic rabbits on the ground outdoors. For rabbit clubs and shows, the AVMA recommends not sharing equipment and supplies, and avoid participating in events where there is illness.3
Rabbit owners and veterinarians can call the USDA APHIS Veterinary Services National Center for Animal Health Emergency Management for assistance with suspected cases of RHDV2 at (800) 940-6524.3 Client handouts with more information about the disease are available online for download from the Cornell University College of Veterinary Medicine Animal Health Diagnostic Center, the USDA, and other sources.