Any of a group of rod-shaped bacteria which create spores (8)
I believe the answer is:
bacillus
(Other definitions for bacillus that I've seen before include "Single-cell organism, can cause illness" , "Type of bacterium" , "A rod-like bacterium, can carry disease" , "CIA bulls, oddly, have a kind of germ" , "Rod-like bacterium, may cause disease" .)