role of spores in the development of c. difficile disease
Clostridium difficile infection C. difficile is transmitted from person to person by the fecal-oral route. The organism forms heat-resistant spores that are not killed by alcohol-based hand cleansers or routine surface cleaning. Thus, these spores survive in clinical environments for long periods. Because of this, the bacteria may be cultured from almost any surface. Once spores are ingested, their acid-resistance allows them to pass through the stomach unscathed. Upon exposure to bile acids, they germinate and multiply into vegetative cells in the colon.
Virulence In the context of gene for gene systems, often in plants, virulence refers to a pathogen's ability to infect a resistant host.[1] In most other contexts, especially in animal systems, virulence refers to the degree of damage caused by a microbe to its host.[2] The pathogenicity of an organism - its ability to cause disease - is determined by its virulence factors.[3] The noun virulence derives from the adjective virulent. Virulent can describe either disease severity or a pathogen's infectivity.[4] The word virulent derives from the Latin word virulentus, meaning "a poisoned wound" or "full of poison."[4][5]