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It's time of year again when EHD is likely to occur

EHD affects deer and can prove fatal. Large concentrations of deer can spread the disease.
EHD affects deer and can prove fatal. Large concentrations of deer can spread the disease.
Duane Sedlock

During this time of year prospective hunters, outdoorsmen and farmers should be alert for deer that may be affected by Epizootic Hemorrhagic Disease (EHD) and should report any suspected cases to authorities. It is the most common infectious disease of white-tailed deer in the Eastern United States. There is no known effective treatment or control of EHD.

EHD is a common viral disease in deer that is contracted from the bite of a species of midge known as Culiocoides sonorensis. Outbreaks strike in late summer or early fall, typically beginning in August and usually ending with the onset of colder weather, which kills the midges. Symptoms of EHD in deer may include difficulty standing, drooling, and emitting foam from the mouth or nose.

Outbreaks of EHD are more likely if the weather has been unusually warm and dry leading to concentrations of deer at whatever water is available, which is where the virus-carrying midges live. EHD outbreaks can also occur from practices like supplemental feeding and placement of mineral blocks which can concentrate deer leading to increased exposure to infected midges.

EHD is not a public health issue and is not a cause for concern about human health. It cannot be transmitted to people, and humans are not at risk by handling infected deer, being bitten by infected midges, or eating infected deer meat, though wildlife officials strongly advise against consuming meat from any game animal that appears ill.

The virus can also infect livestock but only rarely causes a mild disease in cattle. People suspecting this disease in cattle should test their animals. Dogs and cats are not affected by EHD virus.

Signs of EHD can be highly variable. White-tailed deer develop signs of illness about 7 days after exposure. They lose their appetite and fear of humans, grow progressively weaker, salivate excessively and finally become unconscious. EHD may have a very short course and may cause death within 1-3 days. Deer may become depressed, feverish and have difficulty breathing. They may also develop swelling of the head, neck, tongue or eyelids. Feverish deer may go to water to drink or attempt to cool off.

There are also longer periods of the disease where deer will survive into winter and eventually die. And it is also possible that a deer which is exposed to the virus is likely to develop immunity to the disease allowing it to recover. For this reason, EHD outbreaks in southern states, which occur more frequently than in the northern states typically have lower mortality rates.

The first occurrence and subsequent identification of EHD occurred in 1955 when several hundred white-tailed deer succumbed in both New Jersey and in Michigan. It was considered a new disease of deer and the name 'epizootic hemorrhagic disease' was suggested to describe its main clinical and pathological features.

Because of its very high mortality rate, EHD can have a significant effect upon the deer population in a given area, reducing numbers drastically. Outbreaks in Michigan have occurred yearly since 2006 and have caused as many as 1,000 deaths a year.

New Jersey has experienced seven confirmed outbreaks of EHD, occurring in 1955, 1975, 1999, 2007, 2010, 2011 and 2012. To report deer with potential signs of EHD in NJ, call one of the following numbers: Office of Fish and Wildlife Health and Forensics: 908- 236-2118; or the Bureau of Wildlife Management: Northern Region, 908-735-7040; Central Region, 609-259-6965; or Southern Region, 609-748-2043.

Outbreaks among white-tailed deer have occurred in Pennsylvania in 1996 (was suspected to be the cause of death in nearly 25 deer in Adams County, but test results in that case were inconclusive), 2002, 2007 and 2011. In August, 2011 the Pennsylvania Game Commission confirmed that EHD was found in deer locally in Northampton County.

In PA, residents are encouraged to call their respective Game Commission region office to report dead or sick deer. Click here for more information on regional offices throughout the state.