Which term describes the place where a pathogen resides and multiplies before spreading?

• A. Pathogen
• B. Reservoir
• C. Portal of Exit
• D. Susceptible Host

Answer: (B)

Recognizing the reservoir: the place where a pathogen normally lives and multiplies before it spreads to other hosts. A reservoir can be a human, an animal, the environment, or an inanimate object where the organism can survive and replicate. This makes it the best descriptor because it identifies the source that sustains the pathogen between transmission events and from which it can reach susceptible hosts. The other terms describe different aspects of transmission: the pathogen is the microorganism itself; the portal of exit is the route by which it leaves the reservoir or host; a susceptible host is someone at risk of infection but not the habitat where the pathogen resides. For example, contaminated water can act as a reservoir for Cholera, allowing the bacterium to persist and reach people who drink it.