Wild rabbits—mostly Desert Cottontails—in the hills above Malibu have started dying from an affliction never before been seen locally. Rabbit hemorrhagic disease, a highly infectious and deadly form of viral hepatitis, has been confirmed in a dead wild rabbit in Ramirez Canyon.
The disease can spread from wild rabbits to domestic rabbits and has a 70 to 100 percent mortality rate.
As reported previously by KBUU News, a caretaker near Ramirez Canyon last month saw a wild rabbit in the throes of dying a violent death. It was shaking, flopping around, had blood coming from its nose, and then it died.
The landowner used gloves to wrap the body in plastic, freeze it, and then contact California Department of Fish and Wildlife. The frozen rabbit was shipped to UC-Davis for testing.
A veterinarian epidemiologist there, Meghan Moriarty, made the diagnosis. She said rabbit hemorrhagic disease had first been detected in California over a year ago in May 2020, then more recently in LA County, but “this is the first time it has been detected in Malibu.”
The disease first emerged in Europe in the 1970s as a form of viral hepatitis. In the 1980s, it spread to China, where it killed 14 million farmed rabbits—all domestic rabbits. A decade ago, a variant emerged in Europe that also kills wild rabbits.
Now the disease has a foothold in wild Malibu. It is strictly a rabbit disease, with no effect on humans, cats, dogs or any other animals. However, to keep it from spreading among rabbits, any dead rabbit and the surrounding area should be treated as a biological hazard.
“If you see wild rabbits that look like they have died from this disease—if there’s blood around the nose or mouth or a large number of dead rabbits in an area, then they shouldn’t be touched,” Moriarty said. “If they do need to be touched … wear gloves and spray down the area with a 10 percent bleach solution. Ideally, carcasses should be buried or county animal control can be called for incineration.”
Because rabbits are such an important prey species, a large die-off would have a significant impact on the food chain in the Santa Monica Mountains, according to National Park Service wildlife ecologist Seth Riley.
“Rabbits are a very important food source to bobcats, coyotes and raptors,” Riley said in an interview with KBUU News.
Residents can report dead wild rabbits to the California Department of Fish and Wildlife, and dead domestic rabbits can be reported to the California Department of Food and Agriculture. These reports help scientists track the disease.
Pet rabbits can be inoculated against the virus. The Filavac vaccine is specifically developed for use against rabbit hemorrhagic disease (also called RHD2), according to various veterinary websites.
Experts warn pet rabbit owners not to feed or use hay or forage grown or stored outdoors in areas where wild rabbits are affected by rabbit hemorrhagic disease and not to allow pet rabbits to graze or roam in the yard if disease is suspected in wild rabbits in the area—as it is in Malibu.