DENVER (CBS4/CNN) – Wild jackrabbits found dead in Adams County tested positive for disease that is highly contagious. and lethal for rabbits. Seventh counties in Colorado have now reported positive cases of Rabbit Hemorrhagic Disease Virus type 2 (RHDV-2).

(credit Colorado Parks and Wildlife)

RHDV-2 can cause internal bleeding and swelling, according to wildlife officials. Affected animals may have blood staining the nose and mouth. Only rabbits, hares and pikas, the diminutive cousin of rabbits, can spread it among each other — humans can’t become infected with it.

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The disease recently appeared in pockets of the Western U.S., and experts warn that if it continues to spread unchecked, it could harm all dozen-plus species of rabbits in the U.S. and the ecosystems they belong to. Wildlife officials day it has already had significant impacts on rabbits and species that prey upon them in Europe. RHDV-2 is considered a foreign animal disease and is of high concern at the state and federal levels.

Last week, a landowner in Adams county found six dead jackrabbits on her property, east of Barr Lake, according to Colorado Parks and Wildlife. Officers submitted the jackrabbits to CPW’s Wildlife Health Laboratory for necropsy. On Thursday they got test results showing the animals were positive for RHDV- 2.

“It is very possible there are other cases out there that haven’t been observed or reported,” said Matt Martinez, Area Wildlife Manager for seven counties surrounding Denver.

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(credit: CBS)

“We will continue to monitor jackrabbits and cottontails in all the counties of the Denver Metro Area,” Martinez stated.

The last RHDV-2 case prior to the one in Adams County was on June 6 of a domestic rabbit from Weld County.

The other six in Colorado with positive RHDV-2 cases are Alamosa (wild cottontail and jackrabbits), El Paso (feral rabbits, wild jackrabbits and domestic rabbit), Montezuma (domestic rabbit), Prowers (wild cottontails), Pueblo (wild cottontails) and Weld (domestic rabbit).

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