The first reported ghouls in the Hio landcame out of the abandoned coal mines near Kron, in which they had thrown the corpses from the Kron Massacre. The current running theory is that the MORTE virus originated in Colum, and mutated to its present form thanks to toxic-driven evolution in Kron. There were several attempts to clear the mines, but the only result was the virus spreading to wounded soldiers. In the end they simply lit the mines ablaze.
Ghouls are destroyed on sight at enclaves and most settlements.