I haven't since many references to a natural treatment for wild animals. For livestock, treatment usually includes oral and injectible meds/antibiotics, foot care and topical treatments. Nutrition probably plays a key role for wild animals. As their condition declines, so does their immune system making them more susceptible to disease or infection. Density can be a factor too; higher densities concentrated on any one place for too long might increase the infection rate. An infected animal could transfer it from 1 site to the next and if other elk are around they may pick it up. I'll keep looking around and if I come across some more info I'll pass it along.
There was also a thread from a few months ago in the General Discussion area on this same issue.