Overview
Rabbit Hemorrhagic Disease (RHD) is a fast-moving, highly contagious viral infection in rabbits that leads to acute liver failure and widespread internal bleeding. The disease is caused by a calicivirus termed the Rabbit Hemorrhagic Disease Virus (RHDV). There are two major strains of concern in domestic rabbits: RHDV1 (also called GI.1) and RHDV2 (GI.2). While RHDV1 affected mostly adult rabbits, the newer RHDV2 strain can cause illness and death in rabbits of any age and is now the dominant variant globally. The virus spreads easily and persists in the environment, which has contributed to major outbreaks in both wild and domestic populations.
Because of the severity and potential for rapid spread, RHD is a reportable disease in many jurisdictions. When you suspect infection in your rabbit, it is important to contact your veterinarian promptly as they may be required to contact state or federal animal-health authorities.

Transmission
RHDV2 spreads through multiple routes, which makes prevention challenging. Key transmission pathways include:
  • Direct contact with infected rabbits or their bodily secretions/excretions.
  • Fomites: contaminated clothing, cages, bedding, food, feed dishes, and surfaces.
  • Insect or vector-borne movement (flies, fleas, possibly mosquitoes) and scavengers or predators moving infected material.
  • Environmental exposure: the virus is extremely resilient—surviving in carcasses, bedding, or contaminated material for weeks to months.
  • Although less common, airborne particles or dust in contaminated environments may contribute to spread, particularly in multi-rabbit or rescue settings.
Because of this broad transmission potential, even indoor-only rabbits may be at risk if exposed indirectly via people, other pets, equipment, or clothing coming from outdoor or wild-rabbit exposure areas. This risk is something that we can discuss on a case by case basis based on your and your rabbit’s lifestyle.

Clinical Signs
The clinical presentation of RHD (especially RHDV2) varies from sudden death with no earlier signs to more protracted illness. Common forms include:
Peracute form
  • Sudden death without warning, often the first sign of infection.
  • May include bloody discharge from nose or genitals.
Acute form
  • Lethargy, anorexia, fever.
  • Respiratory distress, discharge from the mouth and/or nose.
  • Cyanosis (blue-tinged mucous membranes), seizures, collapse.
Subacute / Chronic form (more common with RHDV2)
  • Slower progression over 1-2 weeks.
  • Jaundice, gastrointestinal stasis (reduced gut movement), weight loss.
  • Neurologic signs such as tremors, ataxia or “paddling.”
  • Eventual death in many cases.
Asymptomatic carriers
  • Some rabbits, particularly young kits, may show no clinical signs yet still survive and shed virus for a period of time, posing risk to other rabbits.
Because the progression can be extremely rapid and subtle, any sudden death in a rabbit—even one appearing healthy minutes before—should raise suspicion for RHD.

Diagnosis
Diagnosing RHD involves a combination of history, clinical signs, and laboratory testing. Key points:
  • Suspect RHD when there is sudden death, rapid illness and compatible signs, especially in areas with known exposure risk.
  • Testing options:
    • PCR (RT-qPCR) for viral RNA to confirm RHDV strain.
    • Necropsy findings: characteristic severe liver necrosis, multifocal hemorrhages in visceral organs.
    • Bloodwork: may show elevated liver enzymes, signs of coagulopathy (disseminated intravascular coagulation), low platelets and other indicators of hepatic failure.
Because of the rapid course, diagnosis is often post-mortem—but early suspicion can help protect other rabbits and guide quarantine measures.

Treatment
At present there is no specific antiviral cure for RHD. Treatment is supportive, and early aggressive care may improve chances, but prognosis is often poor once clinical signs are established. Typical management includes any combination of fluid therapy, correction of electrolyte abnormalities, hepatoprotectants, gastroprotectants, and anything else necessary to manage secondary complications.
Given the high fatality rate for unvaccinated rabbits and limited effectiveness of treatment once disease is clinical, prevention remains vastly more effective than attempting cure.

Prevention
Prevention combines vaccination, biosecurity, and environmental control.

The RHDV2 vaccine is conditionally approved currently, and YVC is one of two sites in the state of Maine licensed for carrying and administering it (as of 2025). We strongly recommend that all rabbits that spend time outdoors or live in homes where other pets go outside, or enter boarding facilities, shows, shelters, or could be exposed to wild rabbits in any way be vaccinated.

The vaccine is an initial series of 2 (2-4 weeks apart) to built the initial immunity, and then updated annually after that.

Additionally, we recommend reducing or eliminating contact with all wild rabbits, and quarantine any new rabbits for a minimum of 14 days prior to introducing them to any housemates. Utilize effective disinfectants where safely and reasonably possible (e.g. diluted bleach, or accelerate hydrogen peroxide); and control insects, birds, rodents, and scavengers that can act as mechanical vectors.


Conclusion
RHD/RHDV2 is a lethal disease of rabbits that requires urgency, vigilance, and prevention. Because treatment options are limited once clinical signs appear, the best strategy is vaccination plus strong biosecurity. If you ever suspect exposure or observe sudden illness in a rabbit—even one kept indoors—act quickly, contact us, and we’ll guide you through appropriate next steps.

At this time the disease is spreading quickly, but has not reliably made it to the Southern Maine area. That said, we at YVC believe it is a serious enough problem that it is better to err on the side of caution and do our best to prevent the disease through vaccination and strict biosecurity.