Yeah, here in Missouri we have had over 3,000 deer die from the blue tongue / fly bite stuff. It's from the drought. Deer aren't able to find water everywhere like normal so they are resorting to main bodies of water like lakes, ponds, creeks, streams, rivers, etc... that is where this type of fly also hangs out. They say that deer down south (texas, arkansas, etc...) are immune to it b/c of the lack of rain down there. We've had alot of farmers find them in the middle of corn fields while combining.
Basically what happens is their mouth swells up and turns a bright purple color. They can't swallow well at all, which means they will dehydrate and starve both. I'm not sure where the hemorage part comes into play, but they are more apt to do that as well.
It's a bad deal.