November 29, 2022 Update – New Detections of Rabbit Hemorrhagic Disease in California

Disease has been detected in domestic and/or wild rabbits in twenty-two California counties - considered endemic in those counties

CDFA taking limited regulatory action

SACRAMENTO, November 29, 2022 – RHDV2 was detected in wild jackrabbits in Colusa, Glenn and Napa Counties in November 2022. It was also detected in domestic rabbits in Solano County on November 3, 2022. It had been previously confirmed in a feral domestic rabbit in Alameda County and in wild jackrabbits in Marin, Solano, and Yolo Counties in October 2022.

Medgene Labs (Brookings, SD) received Emergency Use authorization from the United States Department of Agriculture’s Center for Veterinary Biologics (CVB) for their experimental vaccine for prevention of Rabbit Hemorrhagic Disease Virus serotype 2 (RHDV2). The new vaccine is a killed recombinant vaccine which is authorized as a two-dose series, with the second dose given 21 days after the first. Rabbit owners should contact their private veterinarian if they are interested in vaccination for RHD. Veterinarians may contact Medgene Labs at info@medgenelabs.com for information about obtaining RHD vaccine.

Rabbit Hemorrhagic Disease Detections in Domestic Rabbits in California 2020-2022

County

Affected
domestic properties

Detected in wild rabbits

Most recent confirmation

Alameda

0

yes

October 18 2022 (feral domestic)

Colusa

0 yes November 2022 (wild)

Glenn

0 yes November 2022 (wild)

Fresno

1

no

August 19, 2021 (domestic)

Inyo

0 yes July 2022 (wild)

Kern

6

yes

June 29, 2021 (domestic)

Los Angeles

18

yes

June 30, 2022 (domestic)

Marin

0 yes October 2022 (wild)

Mendocino

1 no June 3, 2022 (domestic)

Mono

0 yes July 2022 (wild)

Napa

0 yes November 2022 (wild)

Orange

0

yes

June 2020 (wild)

Riverside

16

yes

June 23 2022 (domestic), June 2022 (wild)

San Benito

0 yes December 2021 (wild) 

San Bernardino

5

yes

March 17, 2021 (domestic); May 2021 (wild)

San Diego

6

yes

May 17, 2021 (domestic); June 2022 (wild)

San Luis Obispo

3

yes

June 3, 2022 (domestic), June 2022 (wild)

Solano

1 yes November 3 2022 (domestic), October 2022 (wild)

Sonoma

1

no

August 19, 2021 (domestic)

Stanislaus

0 yes June 2022 (wild)

Ventura

5

no

May 7, 2021 (feral domestic)

Yolo

0 yes October 2022 (wild)

Grand Total

63

 

 

RHDV2 is a serious and extremely contagious viral disease of rabbits. Morbidity and mortality rates are high in unvaccinated animals; in some groups of infected rabbits, most or all may die. The disease has been known to cause dramatic declines in some wild rabbit populations.

The disease has been detected in wild rabbits in most western states. CDFA considers the disease endemic to these areas, triggering limited regulatory action when domestic rabbits become infected, and focusing on assisting owners to protext their rabbits. Test-positive domestic rabbits are quarantined, and owners are provided information on how best to reduce spread of the virus. Restrictions on rabbits moving into California are still in effect.

Rabbit owners are urged to protect their animals by preventing contact with wild rabbits and jackrabbits, and if possible, keep domestic rabbits indoors in areas with known disease. House outdoor rabbits off the ground when possible. Owners are also asked to practice biosecurity to prevent accidentally spreading the RHDV2 virus to their rabbits. Avoid feeding hay grown or stored outdoors in areas where wild rabbits are affected. Apparently healthy rabbits can spread the disease, so rabbit owners should avoid direct or indirect contact between their animals and other rabbits.

Please report dead domestic rabbits to CDFA at 909-947-4462. Consult your private veterinarian if your domestic rabbit is sick. Report dead wild rabbits to the California Department of Fish & Wildlife at https://wildlife.ca.gov/Conservation/Laboratories/Wildlife-Health/Monitoring/Mortality-Report.