Hemorrhagic Disease (HD) is a common viral disease in deer that is transmitted by biting midges belonging to the genus Culiocoides. Hemorrhagic disease may be caused by one of two closely related viruses, including Epizootic Hemorrhagic Disease (EHD) virus or Bluetongue Virus (BT). Hemorrhagic disease outbreaks in New Jersey typically occur in August through October and end with the first significant frost, which kills the midges. Ten EHD outbreaks have occurred in various parts of New Jersey since 1955 (see Figure below), and the first documented case of BT occurred in deer in 2014.

Historically HD Outbreaks in New Jersey deer have been related to EHD virus. In 1955, 1975 and 1999 outbreaks were caused by the EHD serotype 1 virus, while outbreaks in 2007, 2010, 2011, 2012, 2021 were caused by the EHD serotype 2 virus. The serotype 2 virus occurs every year in parts of the southern U.S., and its recent occurrences in New Jersey raise concern that it may persist and occur more frequently here as well. In 2014, New Jersey had its first documented case of BT in free-ranging deer in Somerset and Morris counties. In 2018 and 2020, EHD serotype 6 (considered a wild type) was documented in the Wallkill River.

In 2021, a significant outbreak of EHD serotype 2 occurred impacting all 21 counties. In total, all 21 counties were impacted, with a total of 217 affected municipalities and 1,409 reported deceased deer. Staff were able to officially confirm EHD in 11 deer within 7 counties.

Because the disease causes fever, sick or dead deer are often seen in or near water, after drinking or attempting to cool off. Other symptoms of HD in deer may include difficulty standing, drooling, lethargy, respiratory distress, emitting foam from the mouth or nose, and swelling of the face, tongue, and neck. Affected deer may also show reduced activity, loss of appetite and develop ulcerations on their tongue.

Clinical signs of EHD may be variable depending on the course of the disease, which may be acute or chronic. As the name implies, the virus (BT and EHD) causes damage to the blood vessels causing hemorrhage within the internal organs. Survivors of the infection or chronically infected individuals may become emaciated in the winter and may exhibit growth interruption or cracks in the hooves.

HD is not a public health issue. Neither EHD nor BT viruses can 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 the Division of Fish and Wildlife strongly advises against consuming meat from any game animal that appears ill

Deer exhibiting any of the above-mentioned signs in late summer and fall, or dead deer observed in or near water should be reported to any one of the following numbers:

Bureau of Wildlife Management:

• Principal Deer Biologist: 609-223-6073 or Jodi.Powers@njdepwptest.net
• Northern Region Deer Biologist: 908-735-7040 ext 209 or Megan.Mills@njdepwptest.net
• Southern Region Deer Biologist: 856-875-6418 or Megan.Mccafferty@njdepwptest.net

Office of Fish and Wildlife Health and Forensics:

• Wildlife Veterinarian: 908-735-6398 or Patrick.Connelly@njdepwptest.net

HD virus rarely infects domestic animals, while BT is a known disease of domestic animals, such as sheep, cattle, goats, and even domestic dogs. To date, no cases of livestock illness related to BT have been reported. People suspecting HD in domestic animals should have them tested for the virus. Additional information may be obtained from the State Veterinarian’s Office at 609-671-6400.

The NJ Department of Agriculture’s Animal Health Diagnostic Laboratory (AHDL) can assist in diagnosing suspected BT cases by offering testing and necropsy services. The AHDL can be contacted by calling 609-406-6999 or e-mailing jerseyvetlab@ag.state.nj.us.