Rabbit Hemorrhagic Disease is considered endemic (or always present) in Australia, New Zealand, Cuba, parts of Asia and Africa, and most of Europe. The US has had cases of RHDVa in Iowa, Illinois, New York, Indiana, Minnesota, and Utah. The last case of RHDVa in Utah was in 2001. RHDV2 was first diagnosed in Europe in 2010. Southwestern Canada experienced its first cases of RHDV2 in 2018, followed by cases in Ohio, Washington, and New York City. In early 2020, a widespread outbreak of RHDV2 emerged in the Southwestern US and northern Mexico, affecting New Mexico, Texas, Arizona, Colorado, Nevada, California, and Utah. It has caused cases in both wild and domestic rabbits.

Rabbits infected with RHD have a short period of high fever and lethargy followed by sudden death in 80—100% of infected rabbits.  The incubation period, or time from infection to signs of illness ranges from 1-3 days.  Death occurs 3-9 days after infection.  In most cases in pet rabbits, the rabbits rarely show any signs of illness and die suddenly within 6-24 hours.  Rabbits may have a fever, nervous signs, difficulty breathing, and refuse to eat.  They may have frothy blood coming from their noses just prior to death.  Some rabbits survive the acute phase, but will continue to shed the virus for at least a month.

The only treatment for RHD is supportive care.  Survival of the acute form of RHD is rare, and chronic cases often succumb to the disease after several weeks.  There are no tests currently within the United States for detecting RHD in live rabbits.  Dead domestic rabbits may be submitted to the Utah Veterinary Diagnostic Laboratory by your veterinarian.

RHD Testing Guidance

RHD virus may be inhaled, eaten, or absorbed through wounds to the skin.  It can survive in the environment for several months, and is usually transmitted by direct contact with infected rabbits or by contact with objects, people, shoes, or clothing that has been contaminated by rabbit bodily fluids or feces.  Rodents, insects, birds, and other animals may also become contaminated with the virus and transfer it to rabbits.

Biosecurity measures you can take to protect your rabbits include:

• Housing

• • Keep rabbits inside if possible on an impermeable and disinfectable surface.
  • If rabbits are housed outdoors, double fence to avoid direct contact with wildlife, especially wild rabbits.
  • House rabbits in hutches or cages off the ground.
  • Do not allow your rabbits to graze or roam in the yard if there are wild rabbits in your area.

• Quarantine new rabbits or rabbits returning from a show

• • Keep rabbits in separate area for 30 days before allowing contact with main colony.
  • Designate one person to care for quarantined animals OR designate separate clothing, footwear, and equipment for the two groups.
  • Care for main colony before quarantined rabbits.

• Human Best Practices

• • Have indoor and outdoor footwear; don’t wear outdoor shoes indoors and vice versa.
  • Wash hands before and after handling or caring for rabbits and between groups.
  • Don’t allow visitors who also have rabbits.
  • Don’t handle others’ rabbits.
  • Handle young rabbits first, then healthy adult animals, then quarantined rabbits, then sick rabbits.
  • Follow disposal guidance for dead rabbits.
  • Do not touch any dead wild rabbits you see.  Contact state wildlife officials.

• Clean and Disinfect Equipment (See USDA C&D guidance)
  • Cleaning
    • Remove all visible organic debris from items to be disinfected (cages, feeding equipment, waterers, footwear, etc.). Items made of wood are best discarded or burned.
    • Wash items thoroughly with soap and water; rinse well and let dry.
    • Allow prolonged exposure to sunlight when possible.
  • Disinfection
    • EPA List of Disinfectants for Use Against RHDV2
    • Saturate by submersion or spray with 10% household bleach (sodium hypochlorite) or 1% Virkon^®S (DuPont)
    • Allow 10 minutes contact, then rinse and let dry before allowing animal contact.
    • Lysol, Clorox wipes, and Odoban are not effective.
• Control disease vectors

• • Flies, rats, cats, dogs, birds, etc. can move the virus around on their feet or body.
  • Fence out scavengers and wildlife, including birds and wild rabbits.

• Feeding

• • Do not put rabbits on the ground to eat grass, etc.
  • Do not collect outdoor forage and browse to feed rabbits or use for bedding; feed commercial pelleted feed where feral and/or wild rabbits are infected with RHDV.
  • Treats can include raw vegetables from grocery stores or grasses grown indoors.
  • Obtain hay from unaffected areas.

• Rabbit Health

• • Monitor rabbits closely for poor appetite, looking limp/depressed, or behaving differently in any way.
  • Call your veterinarian ASAP if signs of illness are observed in rabbits.

• • Consider RHDV2 vaccination where available.
  • Do not rely solely on vaccination for disease prevention; continue biosecurity practices daily.
  • Minimize rabbit stress by providing clean environment, required nutritional quality and quantity, fresh air, clean water, and adequate space.

• Report all unusual sickness and/or death to your veterinarian or the Utah State Veterinarian.

Rabbit events or meetings with live rabbits can contradict several biosecurity recommendations. Biosecurity practices are always a good idea, not just for RHD, but more common contagious conditions such as Pasteurella and mites.   Outdoor rabbits are at the highest risk for diseases like RHD.  Indoor rabbits cared for with excellent biosecurity practices are at very low risk of RHD and other diseases.

Rabbits co-mingled at club meeting, shows, etc. have greater risk of contracting snuffles from an infected rabbit compared to RHD. Risk of disease transmission could be reduced at club meetings by only having rabbits from one premises present per meeting. All club members must wash hands before and after handling rabbits and arrive at the meeting site with clean clothing and clean/disinfected footwear. After returning home, they should change clothes and footwear and wash their hands before caring for their own rabbits.

The Utah State Veterinarian has the authority to set health requirements for fairs and shows in Utah, and if the risk of disease spread is too great, rabbit shows may be cancelled or postponed.  Individual shows may also set their own requirements for protecting exhibitors and their rabbits.  If traveling to another state for a show, check with the state of destination for their requirements.  Some states may require a certificate of veterinary inspection (health certificate) or have additional restrictions for rabbits from states with RHD.

• Showing
  • Judges and veterinarians should change gloves or wash hands between animals.
  • Do not share show carpets; designate one per animal.
  • Be sure the show has excellent vector control. Flies, rats, cats, dogs, birds, etc. can move viruses around on their feet and body.
  • Avoid common grooming stations.

• Animal health

• • Monitor rabbits closely for signs of illness (poor appetite, looking limp/depressed, behavioral changes, etc.) and seek immediate veterinary care.

• • Isolate sick rabbits in a designated isolation area.

• Housing
  • Keep show rabbits in cages off the ground.
  • Do not allow nose-to-nose contact between rabbits at an exhibition.
  • Clean and disinfect cages, waterers, and feed bowls daily.
  • Do not allow rabbits to exercise in common areas on exhibition grounds.

• Human best practices
  • Wash hands frequently, especially before and after handling animals.
  • Wear different clothes and shoes at shows than at home
  • After returning from an exhibition, change clothing and footwear and wash hands before contacting main colony.
  • Wash show clothing and C&D footwear ASAP after returning home.
  • Do not share equipment, grooming tools, feeding implements, etc.
  • Wash hands before and after handling or caring for rabbits and between groups.
  • Don’t handle others’ rabbits.

• Clean and disinfect equipment = (See USDA C&D guidance)

• • Cleaning
    • Remove all visible organic debris from items to be disinfected (cages, feeding equipment, waterers, footwear, etc.). Items made of wood are best discarded or burned.
    • Wash items thoroughly with soap and water; rinse well and let dry.
    • Allow prolonged exposure to sunlight when possible.
  • Disinfection
    • EPA List of Disinfectants for Use Against RHDV2
    • Saturate by submersion or spray with 10% household bleach (sodium hypochlorite) or 1% Virkon^®S (DuPont).
    • Allow 10 minutes contact, then rinse and let dry before allowing animal contact.

• Feeding
  • Obtain hay from unaffected areas.
  • Keep feed covered or in a container with a lid while at shows.
  • Do not share feed, water, or treats with other exhibitors.

• Going home
  • Clean and disinfect cages, equipment, and transportation surfaces after shows.
  • Isolate all rabbits returning from an event for 30 days before returning them to the main colony.

• Feed, handle, and care for young rabbits first, then healthy adult animals, then quarantined rabbits, then sick rabbits.
  • Report unusual illnesses or death to your veterinarian or the Utah State Veterinarian.

Is there a vaccine for RHD?

Yes, Medgene has developed an RHDV2 vaccine that has received emergency use approval.  Now that we have a vaccine available in the United States, we will no longer approve import of the Filavac and Eravac vaccines from Europe.

Is the vaccine available in Utah?

Yes, any veterinarian in Utah can order the vaccine from Medgene.

Can vaccinated rabbits spread RHD?

It is not known if rabbits vaccinated with the Medgene vaccine can shed RHD.  Both vaccinated and unvaccinated rabbits can carry the virus on their feet, hair, or whiskers and move the virus (just like other animals, human feet, car tires, or equipment).  It is important to practice good biosecurity whether your rabbits are vaccinated or not.

Will the vaccine protect my rabbits?

No vaccine is 100% effective, so it is important to practice good biosecurity, even if your rabbits are vaccinated.  The vaccine takes 14 days after the second dose to provide full immunity from the disease, so be extra-vigilant while your rabbit is not fully protected.

Do I need to give a vaccine booster?

The Medgene vaccine requires a booster dose 21 days after the first dose.  An annual booster may also be required.

Are there any side effects from vaccination?

Vaccine side effects may include lethargy, fever, and swelling at the vaccination site. The vaccine has not been tested in pregnant or nursing rabbits.

Is there a withdrawal time in meat rabbits?

Yes.  The USDA requires a 21-day meat withdrawal period for rabbits intended for meat consumption.

Where can I get more information about the Medgene RHD vaccine?

The Medgene website is: https://medgenelabs.com/rhdv2/

USEFUL LINKS

Low Frequency RFID Readers

EPA List of Disinfectants for Use Against RHDV2

UDAF Rabbit Hemorrhagic Disease Factsheet

UDAF Guidance for Positive Premises

USDA Rabbit Hemorrhagic Disease Emerging Risk Notice

USDA RHD Factsheet

USDA RHD Vaccination FAQ

USDA RHD Cleaning and Disinfection Guidance

House Rabbit Society RHD Page

American Rabbit Breeders Association

California Department of Food and Agriculture RHD Biosecurity Recommendations