PIERRE, S.D. – South Dakota Game, Fish and Parks (GFP) has documented deer mortalities in 2021 due to hemorrhagic disease, also known as epizootic hemorrhagic disease (EHD) or blue tongue. To date, EHD has been confirmed by laboratory analysis in deer from Beadle, Harding, Pennington, and Perkins counties. Additional reports of dead deer are coming in from other areas as well, many of which likely succumbed to EHD.
The virus is spread by a biting midge and causes extensive internal hemorrhaging in infected animals. Many deer exhibit no clinical signs and appear perfectly healthy, while others may have symptoms such as respiratory distress, fever, and swelling of the tongue. With highly lethal strains of the virus, deer can be dead within 1-3 days. Affected deer are often found near low lying areas or water, likely due to the deer attempting to combat the high fever.
This disease is common in white-tailed deer and is typically detected in late summer or early fall. Minor deer losses to EHD can occur in any given year in South Dakota, but weather and habitat conditions will dictate the severity of the disease. EHD outbreaks can be locally severe, but rarely affect a high proportion of the deer population in a management unit. Deer can continue to succumb to this disease until a hard freeze reduces the midge populations that carry the disease.
EHD is not infectious to humans. For more information on the EHD virus visit https://gfp.sd.gov/epizootic-hemorrhagic-disease/.
“To assist GFP in monitoring this situation, we are asking landowners and hunters who encounter dead or sick deer to report those findings to their local conservation officer or GFP office,” stated Wildlife Division Director Tom Kirschenmann. “This information will assist wildlife managers in making recommendations to respond accordingly.”