Bluetongue disease is taking its toll on the deer population in parts of Kentucky.

Hemorrhagic Disease is a bug-borne illness that affects white-tailed deer. It is caused by bluetongue virus, which causes lethargy, weakness, swelling in the head area and internal bleeding. The disease cannot be transmitted to humans.

As of Sept. 19, 3,518 cases have been reported in the state, according to the Kentucky Department of Fish & Wildlife Resources. The impact has been the greatest in the state's eastern counties, with nearly 500 cases in Pike County alone.

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Several southern Kentucky counties are seeing large numbers of cases, too.

The disease has killed 115 deer in Knox County, 73 in Bell County and 56 in Whitley County so far this year. The disease only affects deer.

Wildlife officials say these outbreaks happen every few years. The last big outbreak was in 2012.

Officials don't expect the disease to cause a major dent in the deer population.

If you see a deer you think died of the disease, you are asked to report it online here.