Rabbit Hemorrhagic Disease Virus – Frequently Asked Questions

What is Rabbit Hemorrhagic Disease?
Rabbit hemorrhagic disease is a highly contagious, severe, and often fatal disease in rabbits.  It is caused by a virus that originated in Europe.  A new strain, RHDV2, became established in the wild (native) rabbit population in the state of New Mexico in February 2020, and it has been slowly spreading across the United States.

What are the signs/symptoms of RHDV2?
The RHDV2 infects and kills rabbits so quickly that it is rare to observe clinical signs. Unfortunately, sudden death is commonly the first sign of a problem. The virus damages the liver, leading to internal bleeding. When observed, clinical symptoms last only a few days, and may include:

  • Bleeding from the nose or other orifices
  • Lethargy and depression
  • Decreased appetite
  • Difficulty breathing
  • Lack of coordination
  • Convulsions

How does the virus spread? How could my rabbit be exposed?
The virus is shed through urine, feces, blood, milk, saliva and mucus from the nose and mouth of infected rabbits. Healthy rabbits get the infection through their mucous membranes (eyes, nose or mouth), and through their digestive tract. They can also get infected through blood-sucking insects. RHDV2 is easily transmitted by “fomites” meaning objects like shoes, clothing, and indoor/outdoor pets. Anything that an infected rabbit touches, urinates on, or defecates on (e.g., plants, bedding, cages, people’s clothes and shoes, etc.) is potentially contagious. The virus is extremely hardy and can last up to 15 weeks on anything contaminated with the urine, feces, saliva, or tissue from an infected rabbit. The virus can also survive freezing temperatures.

If my rabbit becomes infected, how likely is it that he/she would die? Is it possible for a rabbit to survive an infection with RHDV2?
Mortality rates range from 50-90%. With support, it is possible to survive the infection.  However, if an infected rabbit survives RHDV2, the rabbit is still contagious and can shed the virus for at least 42 days.

Can Rabbit Hemorrhagic Disease infect humans?
No, it does not affect humans.

What can I do to protect my rabbit from this disease?

  • Don’t let your rabbit outside
  • Take off your shoes when you come in the house
  • Prevent mosquitoes and flies with window and door screens
  • Keep cats indoors, so they can’t bring in the virus from outside.
  • Walk dogs on-leash to ensure they don’t directly interact with wild rabbits or their droppings.  Wash off their paws when they come inside.
  • Designate separate areas in the house for your dogs, and block their access to your bunnies.
  • Use monthly flea prevention on all animals in your home (ask your vet about rabbit-safe flea products).
  • Make sure all hay was stored for 4 months before use
  • Wash greens/veggies thoroughly (ideally for 2 minutes)
  • Vaccinate your rabbits for RHDV2.

Is there a vaccine for RHDV2?
Yes, Medgene Labs has developed a new vaccine and gained emergency use authorization by the USDA after review of current safety and challenge information.

What kind of vaccine is the Medgene Labs vaccine?
Medgene Labs vaccine is an inactivated (killed) recombinant subunit vaccine that builds immunity to RHDV-2 specific antigenic proteins in the rabbit. The immune system sees the RHDV-2 protein and learns to protect the rabbit from the virus.

How is the vaccine given?
The vaccine is administered through a subcutaneous (under the skin) injection. Two doses are needed, with the second (booster) dose being delivered 21 days following the initial dose.

How effective is the vaccine in preventing RHDV-2?
The vaccine has been shown to be highly effective in preventing death in a CVB-approved efficacy challenge study conducted at university facilities. 100% of rabbits who were fully vaccinated survived when challenged directly with RHDV-2 live virus.

Will my rabbit possibly infect other rabbits after being vaccinated?
No. This vaccine only uses parts (proteins) of RHDV-2 to build immunity. It is impossible for a rabbit that receives this vaccine to shed the virus, because it doesn’t contain the full RHDV-2 virus.

How long does it take for the vaccine to be effective?
The vaccine should be fully protective 14 days after the second vaccine booster, which would be 35 days after the first dose.

How effective is a single dose of the vaccine?
Due to the urgent need of a US RHDV-2 vaccine, Medgene has focused on producing the most protective and safest vaccine possible; at this time that requires a two-dose series 21 days apart.

What side effects should I expect?
Rabbits may develop a small swelling at the site of the injection, develop a mild temporary fever, or be lethargic for a day or two.

How young can I administer the vaccine?
This vaccine has demonstrated safety when given at 4 weeks of age.

Is it safe for pregnant and nursing does?
A full study on the safety in nursing and pregnant does has not yet been completed.