Deadly Hemorrhagic Disease That Kills 80 Percent of Rabbits Spreading Across U.S.

A deadly disease fatal to rabbits in around 80 percent of cases is spreading across the U.S., with new cases now confirmed in Florida.

Rabbit Hemorrhagic Disease does not affect human health but is highly infectious and frequently fatal to both wild and domestic rabbits, with a fatality rate of between 80 and 100 percent.

The strain of Rabbit Hemorrhagic Disease currently affecting the U.S. is known as RHDV2. This is a virus that affects rabbits over a three to nine-day incubation period.

Symptoms in infected animals including lethargy, weight loss and hemorrhages from various orifices such as the nose or eyes. It is spread by coming into direct contact with live or dead infected rabbits, or by contaminated surfaces such as their bedding. It can also be spread by rabbits orally and through skin trauma.

Death in infected rabbits typically occurs within one to three days.

The presence of the RHDV-2 strain of the virus was discovered in multiple states last year, and new cases identified in New York and Florida suggests it is continuing to spread in the U.S.

According to Florida's Department of Agriculture and Consumer Services (FDACS), two cases of the disease have been confirmed—one in Lake County and another, more recent case, in St John's County.

The New York Department of Agriculture and Markets (NASDA) said on December 15 that a case of the virus had been confirmed in a domestic rabbit in Montgomery County. It said it there was an ongoing investigation into the source of the infection.

"This is the second occurrence of RHDV2 in New York," the NASDA statement said. "The first cluster of cases was in New York City in March 2020. The virus was quickly identified, isolated and eradicated."

It said concerned pet owners should contact their vets about the use of a vaccine that has been approved by the U.S. Department of Agriculture (USDA.)

The FDACS has also approved the use of vaccine against RHDV-2. "FDACS is approving the use of the USDA experimentally approved Medgene vaccine which targets the U.S. strain of RHDV-2," it said in a statement released January 7. "In addition, importation approval of the European RHDV vaccines by licensed, accredited veterinarians began in July. Rabbit producers should contact their veterinarian regarding vaccinating their rabbits for RHDV-2."

FDACS said the virus has been confirmed in 17 states. Along with Florida, these include Arizona, California, Colorado, Georgia, Idaho, Kentucky, Mississippi, Montana, Nevada, New Mexico, New York, Oregon, South Dakota, Texas, Utah, Wyoming.

Vets in Florida have started vaccinating animals against the disease. Susan Kelleher of the Avian and Exotic Animal Hospital in Deerfield Beach, Florida, told WPTV news on January 18 she had held a vaccine clinic for Floridians to get their rabbits inoculated against the disease.

"They die suddenly from a high fever and bleeding from the nose and mouth," she told the station. "We were able to get special permitting for the vaccine. The fact that it has gone all the way across the United States in two years demonstrates how contagious that is."

Advice published by the USDA in 2020 said the disease can spread rapidly and was highly resistant to extreme temperatures: "It can be spread through direct contact or exposure to an infected rabbit's excretions or blood. The virus can also survive and spread from carcasses, food, water, and any contaminated materials. People can spread the virus indirectly by carrying it on their clothing and shoes."

Desert Cotton Tail Rabbit in New Mexico
A young desert cotton tail rabbit in New Mexico. The RHDV2 is highly infectious and deadly to both wild and domestic rabbits. Robert Alexander / Contributor/Getty Images