In the chain of infection, what is a reservoir host?

• A. A nonliving object (fomite) that passively carries pathogens from one surface to another
• B. A living organism that harbors a pathogen and provides a site where it can survive and multiply, often serving as a source of infection
• C. The route by which a pathogen leaves the host, such as respiratory droplets or blood
• D. The specific body site through which a pathogen enters a new susceptible host, such as the respiratory tract

Answer: (B)

Verified step by step guidance

1. Understand that the chain of infection describes the sequence of events that allows a pathogen to spread from one host to another.
2. Identify that a reservoir host is the place or organism where the pathogen normally lives, grows, and multiplies.
3. Recognize that a reservoir host is typically a living organism, which can be human, animal, or sometimes an environmental source, that maintains the pathogen over time.
4. Differentiate the reservoir host from other components such as fomites (nonliving objects), portals of exit (routes pathogens leave the host), and portals of entry (routes pathogens enter a new host).
5. Conclude that the reservoir host is crucial because it serves as the source from which other individuals can become infected.