Virulence

Virulence is the capacity of a microorganism to cause disease in its host. Virulence is a measure of the severity of a disease caused by a particular strain of the organism. Different strains of the same species can have different levels of virulence, and some species may even have harmless strains. The virulence of an organism is determined by the number and types of virulence factors it possesses. Virulence factors may include toxins, enzymes, or other molecules that allow the organism to cause disease in its host. Understanding the virulence factors of an organism can help scientists develop new treatments and preventative measures for diseases caused by that organism.