Epizootic Hemorrhagic Disease

Epizootic Hemorrhagic Disease (EHD) is common to whitetail deer and comes from a virus carried by biting gnats (commonly referred to as "No-See-Ums") that live in or near water and wet, muddy areas. The disease is transmitted to deer that frequent such areas in late summer and early fall during the warm, dry weather. White-tailed deer develop signs of illness about 7 days after exposure to the virus. Outbreaks will end with the onset of cold weather. The first hard frost kills or drives the majority of the infected insects into winter inactivity.

EHD is a very serious, often fatal disease affecting whitetail deer and other ruminants. Most deer that die do so around water because they develop high fevers and seek water to cool their bodies.

The Three Forms of Hemorrhagic Disease

  1. Peracute - Most dramatic and characterized by its rapid onset. Death often occurs within 24 hours.
  2. Acute - the classic form of Hemorrhagic disease. Deer live somewhat longer.
  3. Chronic - typified by growth interruptions on the hooves. Deer often survive this form.

Deer in the early stages of EHD may appear lethargic, disoriented, lame, or unresponsive to humans. Blood vessels are damaged leading to numerous small and large hemorrhages causing visible symptoms like ulcers in the tissues of the mouth and tongue accompanied with excessive blood-tinged salivation and nasal discharge.

Other Symptoms Include:

  • Swelling of the face, tongue, neck and eyes
  • Lack of appetite
  • Hemorrhaging of the skin, stomach, heart and testicles
  • Difficulty breathing
  • Cracked and overgrown hoofs
  • High fever

It’s important to note that humans are not at risk by handling infected deer, eating venison from infected deer, or being bitten by infected midges.

EHD in New York State

The New York State Department of Environmental Conservation (DEC) has confirmed that approximately 100 white-tailed deer were found dead in the Town of Clarkstown, Rockland County, in August of 2011 due to an outbreak of EHD.

EHD was last confirmed in New York in 2007 in Albany and Niagara Counties. The DEC will continue to monitor the situation. Sightings of sick or dying deer should be reported to the nearest DEC Regional Office or to an Environmental Conservation Officer.

Back to Deer Diseases from Epizootic Hemorrhagic Disease

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