Virulence and virulence factors


Virulence is not synonymous with pathogenicity (see also pathogenicity above), but describes the degree of damage that the pathogen has caused the host animal. A highly virulent bacterium is very contagious and/or gives severe symptoms. Thus, the infectious dose (ID) is lower for a high-virulent than for a low-virulent microorganism.

Virulence factors

Virulence factors are the components that bacteria produce in order to:

Virulence genes are the genes encoding for virulence factors or components required for the synthesis of virulence factors.