DEC Confirms Spread of Epizootic Hemorrhagic Disease

The New York State Department of Environmental Conservation (DEC) today confirmed Epizootic Hemorrhagic Disease (EHD) in Columbia, Dutchess, Greene, Nassau, Oswego, Suffolk, and Ulster counties. DEC is tracking suspected cases in Albany, Jefferson, Oneida, Orange, Putnam, Rensselaer, Rockland, Sullivan, and Westchester counties and new reports of dead deer to track the spread and estimate the number of deer succumbing to this disease. To date, DEC has received reports of approximately 700 dead deer.

In New York, EHD virus is typically a fatal disease for deer that is transmitted by biting midges, small insects sometimes called no-see-ums or ‘punkies.’ The disease is not spread from deer to deer and humans cannot be infected by deer or bites from midges.

EHD virus was first confirmed in New York deer in 2007, with relatively small outbreaks in Albany, Rensselaer, and Niagara counties, and in Rockland County in 2011. From early September to late October 2020, a large EHD outbreak occurred in the lower Hudson Valley, centered in Putnam and Orange counties, with an estimated 1,500 deer mortalities.

Once infected with EHD virus, deer usually die within 36 hours. EHD outbreaks are most common in the late summer and early fall when midges are abundant, although initial cases this year were detected in late July. Signs of the EHD virus include fever, hemorrhage in muscles or organs, and swelling of the head, neck, tongue, and lips. A deer infected with EHD may appear lame or dehydrated. Frequently, infected deer will seek out water sources and many succumb near a water source. There is no treatment or means to prevent EHD. Dead deer do not serve as a source of infection for other animals. EHD has been in New York since July, and has had time to circulate and spread prior to the first killing frosts. Consequently, it has been more widespread this year than during previous outbreaks.

EHD outbreaks do not have a significant long-term impact on regional deer populations, but deer mortality can be significant in small geographic areas. EHD is endemic in the southern states, which report annual outbreaks, so some southern deer have developed immunity. In the northeast, EHD outbreaks occur sporadically and deer in New York have no immunity to this virus. Consequently, most EHD-infected deer in New York are expected to die. The first hard frost is expected to kill the midges that transmit the disease, ending the EHD outbreak.

Sightings of sick or dead deer suspected of having EHD can be reported to DEC via a new online EHD reporting form (link leaves DEC’s website), also available via DEC’s website or by contacting the nearest DEC Regional Wildlife Office. DEC will continue to collect samples from deer and analyze data from deer reports to determine the extent of the outbreak. In addition, DEC has alerted Department of Agriculture and Markets veterinarians in the region to be aware of the disease and to report suspicious cases among captive deer.