Which of the following is a host-related disease determinant?

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

Answer: (A)

Host-related determinants are characteristics of the person that influence their risk of infection and the severity of disease. Nutritional status directly affects immune function, mucosal barrier integrity, and overall ability to fight infections. When nutrition is good, the immune system can respond more effectively; when it’s poor, immune responses are weaker and susceptibility and disease severity can rise. This makes nutritional status a clear example of a host factor.

In contrast, how a disease is transmitted or spreads depends on the environment and the pathogen’s biology: the transmission route describes exposure dynamics, environmental humidity affects pathogen survival outside the host, and the viral mutation rate is a property of the pathogen itself. Hence, these are not host-related determinants.