Outbreak of viral deer disease that leads to die-offs reported in Southwest Michigan - EHD confirmed in one

[Mary Wilson]

Published: Sep. 06, 2024, 10:12 a.m.
By Lucas Smolcic Larson

ST. JOSEPH COUNTY, MI - A common viral disease that can lead to localized die-offs of deer has been confirmed in Southwest Michigan, with early reports indicating 2024 could see a “significant outbreak” in pockets of the deer population, state wildlife officials say.

The Michigan Department of Natural Resources confirmed a case of epizootic hemorrhagic disease, or EHD, in a free-ranging white-tailed deer in St. Joseph County, south of Kalamazoo, ending a three-year hiatus in the county for EHD, the agency announced on Friday, Sept. 6.

The DNR has also received reports of over 120 probable cases of EHD in the past several weeks, primarily from counties in the southwestern Lower Peninsula, and several are awaiting lab confirmation, officials said. ...

https://www.mlive.com/environment/2024/09/outbreak-of-viral-deer-disease-that-leads-to-die-offs-reported-in-southwest-michigan.html

[Mary Wilson]

Epizootic hemorrhagic disease confirmed in white-tailed deer in 11 southwest Michigan counties

October 03, 2024
Department of Natural Resources

Since early September, the Michigan Department of Natural Resources Wildlife Health Section has confirmed epizootic hemorrhagic disease, or EHD, in the wild deer population across 11 counties in southwest Michigan. The affected counties include Barry, Berrien, Branch, Calhoun, Cass, Hillsdale, Kalamazoo, Kent, Ottawa, St. Joseph and Van Buren. ...

https://www.michigan.gov/dnr/about/newsroom/releases/2024/10/03/ehd-confirmed-in-white-tailed-deer-in-11-southwest-michigan-counties

[Mary Wilson]

Epizootic Hemorrhagic Disease (EHD) in White-Tailed Deer

Department of Natural Resources

Description
Epizootic hemorrhagic disease (EHD) is an acute, infectious, often fatal viral disease of some wild ruminants. This malady, characterized by extensive hemorrhages, has been responsible for significant epizootics in deer in the northern United States and southern Canada. A similar hemorrhagic disease called bluetongue also occurs throughout the U.S. and Canada. The two diseases are antigenically different. ...

Clinical Signs
Clinical signs of EHD and bluetongue are very similar.

White-tailed deer develop signs of illness about 7 days after exposure. A constant characteristic of the disease is its sudden onset. Deer initially lose their appetite and fear of humans, grow progressively weaker, often salivate excessively, develop a rapid pulse and respiration rate, and fever (affected animals frequent bodies of water to lie in to reduce their body temperature) and finally become unconscious. Hemorrhage and lack of oxygen in the blood results in a blue appearance of the oral mucosa, hence the name 'bluetongue'. Eight to 36 hours following the onset of observable signs, deer pass into a shock-like state, become prostrate and die. ...

Treatment and Control
There is no known effective treatment or control of EHD. Theoretically, an oral vaccine could be developed for administration through a supplementary winter-feeding program, but this is presently impossible, impractical and unwarranted.

Significance
Because of its very high mortality rate, EHD can have a significant effect upon the deer population in a given area, reducing numbers drastically. A common observation in outbreaks involving large numbers of deer is that they are single epizootics which do not recur. Die-offs involving small numbers of deer occur almost annually, and the disease appears to be enzootic in these areas.


Photos


First figure: Edema (yellowish fluid) underneath the skin. Second figure: Hemorrhages on the organs, diaphragm, and musculature.

https://www.michigan.gov/dnr/managing-resources/wildlife/wildlife-disease/wdm/ehd