Final answer:
Factors of host susceptibility related to the pathogen are the traits of the pathogen that facilitate infection, such as surface proteins for binding to host cells, rather than factors like age, gender, or nutrition, which relate to host condition.
Step-by-step explanation:
The question posed is concerned with the factors of host susceptibility that are related to the pathogen. Factors such as age, gender, and nutrition can indeed influence how susceptible an individual is to infectious diseases. However, these factors are not directly related to the pathogen itself; instead, they refer to the host's condition and how it might affect the immune response to a pathogen. Host susceptibility factors that are directly related to the pathogen include traits such as its virulence factors. For example, a surface protein allowing the pathogen to bind to host cells is a virulence factor of a pathogen, as this facilitates infection.
Furthermore, the level of susceptibility in individuals to bacterial infections can be influenced by a myriad of factors, not solely related to the pathogen's ability to cause damage (its pathogenicity). This results from the interaction between the microbe's virulence factors, such as capsules in fungi like Cryptococcus, and the individual's immune defense, which may be affected by conditions such as undernutrition or environmental exposure to pathogens.
The outcome of an infection is ultimately determined by these interactions, highlighting the importance of understanding the host-pathogen relationship for predicting which individuals may be at greater risk and for developing preventative strategies against infectious diseases.