When his boss called to complain that the time-sensitive documents he was waiting for still hadn't arrived, Victor worried that the courier responsible for delivery may secretly be on their competitor's payroll and had sabotaged them on purpose.
Virulence factors are molecules produced by pathogens (bacteria, viruses, fungi and protozoa) that contribute to the pathogenicity of the organism and enable them to achieve the following: 1  colonization of a niche in the host (this includes attachment to cells). 2  immunoevasion, evasion of the host's immune response.
The ability of bacteria to cause disease is described in terms of the number of infecting bacteria, the route of entry into the body, the effects of host defense mechanisms, and intrinsic characteristics of the bacteria called virulence factors. Colonization. 2  Some virulent bacteria produce special proteins that allow them to colonize parts of the host body. 3  Helicobacter pylori is able to survive in the acidic environment of the human stomach by producing the enzyme urease.