Which of the following is a host-related determinant listed in the material?

• A. Immunologic status
• B. Transmission route
• C. Environmental humidity
• D. Viral mutation rate

Answer: (A)

Host-related determinants are the characteristics of the person that affect susceptibility to infection and how the disease might progress. Immunologic status fits this category because it directly reflects how well the immune system can respond to a pathogen, influencing both the likelihood of infection and the severity of outcomes. For example, individuals with weakened immune systems—due to age, certain diseases, medications, or conditions like HIV—are more prone to infections and may have more severe or atypical courses.

The other options describe factors outside the person. Transmission route is about how the pathogen moves between people, which involves the agent and the environment. Environmental humidity is an external environmental factor that can influence transmission dynamics but isn’t a property of the host. Viral mutation rate is a characteristic of the pathogen itself, not of the person who becomes infected.

So immunologic status is the host-related determinant listed.