RHDV is a deadly disease that can infect rabbits via a virus and affects the liver and blood vessels. The virus belongs to the calicivirus family, that can remain in the environment for up to 3.5 months and is capable of surviving both freezing and very hot temperatures.
Its original strain emerged in China in 1984, with a second strain called RDHV2 found in France in 2010 and which has continued to spread throughout Europe and now the US and Western Canada.
RDHV2 is worrisome for rabbit owners because it is easily spread through direct contact with an infected rabbit, their feces or other bodily fluids, as well as through contaminated items such as bedding and clothes. While this virus does not affect other animals, they can act as a route for the transmission of the virus if they have been in contact with an infected rabbit. RHDV2 is also not zoonotic, meaning it can’t be transmitted to humans, so there is no concern of owners catching this virus from their rabbits.
Once a rabbit catches RHDV2 they will likely show signs within 1-9 days. Unfortunately at this time, there is no cure for this disease and so treatment involves providing supportive care for the affected rabbit. Rabbits that are fortunate to survive RHDV2, will continue to shed the virus for at least 42 days if not longer. It is also very difficult to detect the disease early on as signs can start suddenly and progress to death very quickly.
• Shortness of breath
• Loss of appetite
• Neurological signs such paddling, seizures, and paralysis
• Blood spots in eyes
• Sudden death
• Bleeding from nose at time of death
In Canada we saw the first cases in 2018 on Vancouver Island and have continued to see more cases of RHDV2 develop in domestic and wild rabbits throughout the US. As of June 2020, there have been no confirmed cases in Ontario. RHDV2 is a notifiable disease by the Canadian Food Inspection Agency (CFIA) and they will be alerted of any potential cases first.
While this disease is quite concerning, experts have agreed that the overall risk for rabbits in an area where there is no current outbreak is very low and this is good news!
There are a variety of preventative measures that are recommended for owners to implement, especially if they are in an area where an outbreak has arisen.
• Keep rabbits indoors
• Wash hands thoroughly with warm water and soap before and after interacting with rabbits
• Change clothes after being outside and leave shoes at the entrance of your home
• Clean and disinfect cages regularly as well as any bowls or toys
• Avoid interacting with rabbits with an unknown history
• Quarantine any new rabbits in your home for 10 days and keep their items away from other rabbits in the household
• Avoid bringing plant material inside
The most effective disinfectants are: bleach (1:10 dilution), potassium peroxymonosulfate (Virkon), and accelerated hydrogen peroxide (Prevail, Accel, and Peroxigard). Note that common household cleaners will NOT kill the virus.
While there are vaccines in Europe for RHDV2, these are currently unlicensed in the US and Canada. If a vaccines from Europe is required, approval through the CFIA is needed along with special permits to import the vaccine so that it can be used in areas experiencing an outbreak. There are pharmaceutical companies in the US working to produce their own vaccine, but it will take over a year before it will be available.
Further information on RHDV2 can be found online at https://rabbit.org/rhdv/ and https://www.inspection.gc.ca/animal-health/terrestrial-animals/diseases/immediatelynotifiable/rhd-or-viral-haemorrhagic-disease-of-rabbits/fact-sheet/eng/ 1526322490096/1526322490704.