The Connecticut Department of Energy and Environmental Protection (DEEP) on Friday announced that a recently-discovered die-off of several deer in the Portland area may be due to hemorrhagic disease, which is one of the most important infectious diseases affecting white-tailed deer. The cause of death could not definitively be determined due to the condition of the dead animals, but the manner in which the deer were found led DEEP biologists to suspect that hemorrhagic disease may be the cause. The DEEP Wildlife Division is encouraging anyone who observes deer appearing emaciated, behaving strangely, or lying dead along the edge of waterbodies to report the information to the DEEP’s 24-hour emergency Dispatch Center at 860-424-3333 or the DEEP Wildlife Division at 860-418-5921. The department is seeking to test other dead deer to confirm the suspicion that hemorrhagic disease is the cause.
In early September, a concerned hunter contacted the DEEP Wildlife Division about several dead deer found along a small waterbody adjacent to the Connecticut River near Sand Hill Road in Portland. The deer were in various stages of decay along the bank, while some were floating in the water. Several additional deer were found less than a mile from that location at another small waterbody. In total, over a dozen deer were found dead in the area.
Hemorrhagic disease is transmitted by biting midges (commonly referred to as sand gnats, sand flies, no-see-ums). First documented in New Jersey in 1955, the disease has been documented in many southeastern states and recently reported throughout the mid-Atlantic region. In 2007, over 20 deer were found dead due to hemorrhagic disease in the greater Voorheesville area of Albany County, New York, approximately 60 miles from the Connecticut border, and another outbreak in New York in 2011 killed nearly 100 deer. In addition to white-tailed deer, other species, such as mule deer, bighorn sheep, pronghorn antelope, and elk, have been documented with the disease in numerous other states.
There has not been a significant negative impact on the long-term health of deer herds in states where the disease has been detected because only localized pockets of animals tend to be infected within a geographic area.
All documented outbreaks of hemorrhagic disease tend to occur during late summer and early fall due to an increase in midge numbers and will cease with the onset of a hard frost, which kills the midges carrying the virus. Outbreaks can range from a few mild cases to high deer mortality.
There are several different forms of hemorrhagic disease, but usually in a new outbreak, the very rapid form occurs and kills the animal within one to three days of infection. Symptoms of hemorrhagic disease in deer include swollen head, neck, tongue, or eyelids with a bloody discharge from the nasal cavity; erosion of the dental pad or ulcers on the tongue; and hemorrhaging of the heart and lungs, causing respiratory distress. Additionally, the virus creates high feverish conditions, leading infected deer to sometimes be found near water sources. Not all symptoms are necessarily present in every infected deer.
Hemorrhagic disease does not infect humans, and people are not at risk by handling infected deer, eating venison from infected deer, or being bitten by infected midges. The disease rarely causes illness in domestic animals, such as cattle, sheep, goats, horses, dogs, and cats. Hunters should observe normal precautions around any sick or strange-acting animals.