Pariah Planet by Murray Leinster - Audiobook

he Planet Savers, by Marion Zimmer Bradley.
Read by Mark Nelson.

The Terran colony on the planet Darkover faces imminent destruction by a plague of the deadly Trailmen's Fever. The only hope is to develop a serum in time, but this requires the cooperation of the elusive native Trailmen, the brilliant parasitologist Dr. Jay Allison, and his split personality. (Introduction by Mark Nelson)