Biochemistry Questions / Discuss the role of virulence factors in bacterial pathogenesis, providing examples of different types of virulence factors and their effects on the host. How do these factors contribute to the distinction between symptomatic and asymptomatic carriage?

Virulence factors are essential in bacterial pathogenesis, allowing the pathogen to invade and cause damage to its host.

For a pathogen to colonise its host, it may employ adhesins, invasins, siderophores, and chemotaxis.

To cause damage to the host, the pathogen may use toxins, proteases, DNases, haemolysins, … These cause pain to the host, causing side effects (diarrhoea, …).

The presence of virulence factors determines whether an infected individual will be asymptomatic or symptomatic. If virulence factors are absent, the patient will likely be asymptomatic.