A slew of dead feral domestic rabbits in Calgary has vets concerned about a potentially fatal disease spreading among their population.
"We're getting reports anywhere from tens of rabbits — to closer to hundreds of rabbits — that are deceased in certain areas," said Dr. Jennifer Davies, a veterinary pathologist at the University of Calgary.
Davies worked on the postmortem examinations of seven dead rabbits in the city, all feral domestic rabbits. She says all were European rabbit descendents, those typically favoured as household pets.
Davies says the rabbits had injuries to their livers that is "highly suggestive" of rabbit hemorrhagic disease (RHD), but not specific to it.
RHD is a sudden, fatal and contagious viral disease affecting rabbits of the oryctolagus cuniculus species, which includes both wild and domestic European rabbits. Rabbits can become sick within a few days of exposure to RHD and often die quickly after getting sick.
It is highly contagious among the species but has not been known to pass on to humans or other animals.
"It's important to keep in mind that this disease does not transmit to people," said Davies.
"Nor does it transmit to our other livestock species or to our other domestic pets such as cats or dogs. This is a rabbit-specific disease."
Confirmation that the rabbits did indeed die of RHD will come from the Canadian Food Inspection Agency (CFIA), which Davies says the lab has submitted samples to.
The CFIA confirmed Thursday they had received the samples at the National Centre for Foreign Animal Disease at their lab in Winnipeg, but that "laboratory results are not yet available."
The U of C's lab confirmed one single case of RHD in May 2022.
Potential to spread
The rabbit deaths were reported in the Manchester Industrial area in Calgary's southeast, and now may be spreading to Seton, says Dr. Leticia Materi, a veterinarian at the Calgary Avian and Exotic Pet Clinic. She says it was also confirmed before in Lethbridge and Edmonton.
"This is sort of the first outbreak of a feral population of rabbits in the city," said Matari.
Matari says that though the virus has historically affected domestic rabbits, there have been recorded cases of it spreading out to other wild populations of rabbits and hares.
Davies says there have been recent outbreaks in Canada of a new rabbit hemorrhagic virus that infects not only European strains of rabbits, but potentially other populations of lagomorphs, including wild rabbits.
She says these rabbit deaths could create concern for rabbit owners and those in commercial rabbit production in the province.
"The virus itself is very highly contagious and highly resistant to the environment as well, so it sticks around for a long time," said Davies.
RHD spread can be mitigated by:
Washing hands before and after handling pet rabbits.
Cleaning rabbit enclosures.
Quarantining a new rabbit away from existing rabbit pets.
Limiting contact with wild rabbits.
RHD symptoms can include shortness of breath, blood spots on the eyes of rabbits, difficulty walking and loss of appetite in the animal.
Dead rabbits in the city can be reported to the Alberta Environment and Parks office, or the City at 311.