News Release

For immediate release: September 17, 2020

Contact: Michael Crusan

Seasonal disease detected in Dakota County reindeer; no known health risks to humans

A reindeer herd on exhibit in Dakota County has eight confirmed cases of Epizootic Hemorrhagic Disease (EHD), which affects members of the deer family, Cervidae. The herd’s veterinarian first noticed a male reindeer appeared sick in late August and when it died, they quickly worked with the University of Minnesota Veterinary Diagnostic Laboratory to determine the cause. The laboratory performed a necropsy on the animal and detected EHD, which was later confirmed by the U.S. Department of Agriculture’s National Veterinary Services Laboratories. Four of the reindeer in the herd are deceased and all eight are laboratory confirmed cases of EHD.

“This virus is transmitted between deer by biting midges, or gnats, which are most active in the fall before they are killed by the first frost of the season,” said Board of Animal Health Assistant Director, Dr. Linda Glaser. “These bugs can’t travel far on their own and farmed cervid owners in this area of the state should take proactive measures to reduce bug exposure by limiting tall grasses, moving animals to higher and drier ground, and consider pest control treatments.”

The Dakota County reindeer herd owner is the Minnesota Zoo in Apple Valley. Zoo staff took a very proactive approach to protect animal health by addressing signs of illness in the herd quickly and requesting official disease testing. They also followed up to reduce risk at their location by mowing the enclosure grass and will treat the area with an insecticide to reduce the gnat population in the exhibit areas. The reindeer and caribou were moved out of the exhibit and are isolated from the remaining cervids at the zoo, which includes moose. Staff are also monitoring the bison herd as bison can also become infected and potentially die from the infection. There is no specific treatment or vaccine available in the U.S.

“The sudden onset of this disease and loss of our reindeer has been an extraordinarily difficult development in a difficult year,” said Minnesota Zoo Director John Frawley. “The health and safety of our guests, staff, and animal collection is the Minnesota Zoo’s utmost priority. Although EHD poses no known health risks to humans, this has been a challenging time for our animal care and veterinary staff who dedicate themselves to the animals at the Zoo. We will continue to work closely with the Board of Animal Health as we monitor our hoof stock populations and take proactive measures in attempts to deter biting midges.”

EHD affects members of the deer family, Cervidae, and there are no known health risks to people. Many different deer species may be infected with EHD, and white-tailed deer are highly susceptible, and experience high rates of mortality. Clinical signs can include fever, anorexia, lethargy, stiffness, respiratory distress, oral ulcers, and severe swelling of the head and neck. Sporadic cases occur in hoof stock such as cattle and sheep. Farmed cervid owners are encouraged to work with their veterinarian to reduce the risk of their herd contracting this disease.


Board of Animal Health:
Michael Crusan, Communications Director

Minnesota Zoo:
Zach Nugent, Communication and Media Relations Specialist