ALBANY, N.Y. (AP) — New York's Department of Environmental Conservation is tracking the spread of a deadly viral disease in deer that's spread by tiny biting flies called midges.

The agency is asking people to report sightings of sick or dead deer to help identify outbreaks.

The viral disease is called Epizootic Hemorrhagic Disease, or EHD. Symptoms in deer include fever, bruises in the mouth and nose, and swelling of the head, neck, tongue and lips. An infected deer may appear lame or dehydrated.

Historically EHD has been common in the southeastern U.S., but it has been increasing in the north.

In New York, the first cases were confirmed in 2007 in Albany, Rensselaer and Niagara counties, affecting several dozen deer. An outbreak in Rockland County in 2011 killed about 100 deer.

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