EHD made it across the continental divide into western Montana (around Missoula) a couple of years ago. Prior to that, from what I've read they'd never seen it. Hundreds of deer died around the Missoula area. It's also started showing up in other states where it was previously not seen. Why? Who knows. It's shown up in Pennsylvania and Kentucky...two states that are really not prone to droughts of any duration. It's also shown up in many other eastern and midwestern states...

The other odd thing about EHD is that it can hit one section/area and wipe out out 80% to 90% of the deer, but 3 miles down the road it might not hit at all. I see this around here quite often. About 5 years ago it pretty much wiped out the whitetails on one section of a creek south of town. 5 or 6 miles further down the creek it didn't hit at all.. It's a strange disease and I really don't think the biologists have quite figured it out.