Yes, one of my neighbors in Oklahoma contracted RMSF, it was pretty bad on her. She's probably still recovering years later. Fortunately I don't get any on me there very often, or even see them very often. I think the fire ants help keep them down. Burning helps too.
None up here in AK, other stuff, but no damn ticks, at least that seem to get on people. I guess there some that get on squirrels and hares, but I've never had the pleasure of seeing one.