Deadly virus detected in two more wild rabbits in San Diego County

A highly contagious and deadly virus targeting wild and domestic rabbits has been detected in two rabbit carcasses found in the Cañada de San Vicente Ecological Reserve in Ramona.

Wildlife officials said two desert cottontails tested positive for the Rabbit Hemorrhagic Disease Virus 2 infection last month.

The virus does not affect humans or domestic animals other than rabbits.

The virus showed up in Mexico and in New Mexico, Colorado, Arizona and Texas before it was detected in a black-tailed jackrabbit carcass found on private property near Palm Springs in May 2020 — its first sighting in California.

The California Department of Fish and Wildlife has reported that the virus has since been detected in San Diego, Orange and San Bernardino counties.

“Infected rabbits and jackrabbits may exhibit no symptoms leading up to their sudden death, or may suffer from fever, swelling, internal bleeding and liver necrosis,” a Fish and Wildlife statement said. “The range of susceptible species in North America is currently unknown, but all rabbit, jackrabbit, hare and pika species are likely susceptible.”

The first confirmed rabbit death from the virus in San Diego County was in Poway in June 2020. Since then, Fish and Wildlife has received 103 reports of one or more dead rabbits by phone or through its online rabbit mortality reporting system, said Deana Clifford, senior wildlife veterinarian with the department.

Since May 2020, Fish and Wildlife has collected and tested 19 rabbits from various locations in San Diego County, Clifford said. Of those, the virus was found in seven rabbits: five desert cottontails — two from Rancho Jamul Ecological Reserve on March 18, the two from Ramona and the first case from Poway — and two black-tailed jackrabbits, in Santee on Feb. 8 and Borrego Springs on March 18, she said.

“The public reporting system has been invaluable for allowing us to track the spread of this new disease in California rabbits,” Clifford said. “Reports of dead rabbits in San Diego County declined in late summer 2020 but have recently increased again.”

That is consistent with other reports suggesting that transmission of the virus appears to decrease in the hottest months of the year, she said.

Bonnie Gallegos, who lives on eight acres in Ramona, said she started noticing dead rabbits on her property about three weeks ago.

She first called the San Diego Humane Society, but was told she needed to talk to Fish and Wildlife officials.

“I was told the virus is highly contagious,” said Gallegos, who has found up to 30 dead rabbits on her property and wants to get the word out about the virus. “If people are aware, they will protect their pet bunnies.”

Residents who find dead rabbits on their property are advised to wear gloves or use a shovel to put the remains in a plastic bag, Fish and Wildlife officials said. Then the plastic bag should be sealed and placed in another plastic bag, which should be sprayed with disinfectant.

Pets, scavengers and other animals can spread the virus on their feet or fur, so officials have released the following guidelines:

• House rabbits should remain inside to minimize potential contact; if outside, they should be kept off the ground.

• Any unusual illness or sudden rabbit deaths should be reported to your veterinarian immediately.

• The virus is highly contagious and can be spread by direct contact with infected animals, their urine and feces, and also through contaminated objects or even insects. Wash hands thoroughly before and after handling rabbits and leave shoes outside.

• Know your hay/feed sources and whether they are near areas affected by the outbreak.
  

• Keep dogs on a leash when outside so they don’t interact with wild rabbits; wash their paws before they come inside. Keep dogs and rabbits in separate areas of your home.

Clifford said her department was monitoring rabbits in several locations to learn how the virus impacts populations of predators such as golden eagles and bobcats that depend on rabbits.

Once the virus is established in wild rabbit populations, “eradication is not possible because the virus can persist in the environment for months and has multiple ways it can be transmitted between rabbits,” she said.

A vaccine available in Europe can protect rabbits from the disease, but it’s not approved for widespread use in the U.S. But the California Department of Food and Agriculture is allowing licensed veterinarians in California to import the vaccine from Europe, Clifford said.

To report sightings of sick or dead wild rabbits, hares or pikas, contact the Fish and Wildlife Investigations Lab at (916) 358-2790 or file an online mortality report by visiting https://wildlife.ca.gov/Conservation/Laboratories/Wildlife-Health/Monitoring/Mortality-Report

City News Service contributed to this report.