The US Department of Agriculture and the Hawai`i Department of Agriculture confirmed rabbit hemorrhagic disease virus, type 2 (RHDV2) in a 4- to 5-year-old neutered male rabbit on a farm in Kula.
This is the first confirmed detection of the disease in Hawai`i, according to a news release. Although fatal to rabbits, RHDV2 cannot be transmitted from animals to humans and does not impact human health.
HDOA’s Animal Industry Division received notice June 14 that nine out of 12 rabbits had died on the Maui farm. A hold order was immediately issued to prevent movement of rabbits and associated cages and materials on and off the farm.
HDOA received confirmation June 17 of RHDV2 infection in the one rabbit tested from the National Veterinary Services Laboratory and a formal quarantine order on the premises was issued by HDOA State Veterinarian Dr. Isaac Maeda.
The duration of the quarantine is expected to be 120 days after premise cleaning and disinfection are completed. The outbreak appears to involve a single premise and is not expected to spread.
RHDV2 is a highly contagious viral disease and is categorized as a foreign animal disease and requires detections to be reported to the USDA and the World Organization for Animal Health.
The disease was first detected in the US in 2018 and has since been detected in New Mexico, Arizona, California, Colorado, Nevada, Texas, Utah Idaho, Wyoming, Montana, Oregon, Tennessee, New York, Kentucky, Mississippi, Minnesota, South Dakota, Georgia and Florida.
The virus is extremely hardy in the environment and can be spread through direct contact between affected rabbits and indirectly by contaminated inanimate objects. Although RHDV2 does not infect species other than rabbits and hares, humans, dogs, rodents and insects may spread the virus via external contamination.
Unlike other rabbit hemorrhagic disease viruses, RHDV2 affects both domestic and wild rabbits.
Many times, the only signs of the disease are sudden death and blood-stained noses caused by internal bleeding. Infected rabbits may also develop a fever, be hesitant to eat, or show respiratory or nervous signs.
The cause of this outbreak remains under investigation. No rabbits brought into the state have been associated with this outbreak.
Since 2020, HDOA has increased surveillance in all rabbits imported into Hawaii from infected states and required enhanced import requirements. Rabbits entering the state are required to be issued a Certificate of Veterinary Inspection within 72 hours of arrival, are inspected by HDOA livestock inspectors upon arrival and are placed on a post-entry quarantine for 30 days.
The State Veterinarian has approved the distribution and sale of the RHDV2 vaccine in Hawaii. Private veterinarians in Hawai`i have also been advised of the outbreak. Rabbit owners should discuss the need for vaccination of their rabbits for RHDV2 with their private veterinarians.
Protect your rabbits by practicing good biosecurity by taking daily steps to keep viruses away from your animals. USDA recommended biosecurity practices include:
• Do not allow other rabbits to contact your rabbits or gain entry to the farm or home.
• Do not allow visitors in rabbitries or let them handle pet rabbits without protective clothing (including coveralls, shoe covers, hair covering, and gloves).
• Always wash hands with warm soapy water before entering your rabbit area, after removing protective clothing and before leaving the rabbit area.
• Do not introduce new rabbits from unknown or untrusted sources.
• Do not add rabbits to your rabbitry from animal shelters or other types of rescue operations.
• If you bring outside rabbits into your facility or home, keep them separated from your existing rabbits for at least 30 days. Use separate equipment for newly acquired or sick rabbits to avoid spreading disease.
• Sanitize all equipment and cages moved on or off premises before they are returned to the rabbitry. We recommend disinfecting with 10% bleach or 10% sodium hydroxide mixed with water.
• Establish a working relationship with a veterinarian to review biosecurity practices for identification and closure of possible gaps.
Hawai`i does not have wild rabbit or hare populations. Should this disease infect wild or loose rabbits, containment and eradication would be very difficult.
Occasionally, reports are received regarding domestic rabbits running loose on properties in Hawaii. Hawai`i state law requires owner and breeders to contain rabbits and hares above the ground. Violations could result in fines, imprisonment, or both.
Any owners or veterinarians experiencing unusual losses of rabbits should contact the HDOA’s Animal Industry Division at (808) 483-7100 or (808) 837-8092.
More information on RHDV2 may be found at the USDA website by clicking here.