Which of the following is the last link in the chain of infection?

The last link in the chain of infection is the susceptible host. In the context of infection control, this term refers to an individual who is vulnerable to the infectious agent due to various factors, such as a weakened immune system, underlying health conditions, or lack of vaccination. The chain of infection outlines the stages through which an infection spreads, and it typically includes the infectious agent, reservoir, portal of exit, mode of transmission, portal of entry, and finally, the susceptible host.

Identifying the susceptible host as the last link is important because once the infection reaches this individual, the cycle can continue if the host becomes infected and can serve as a new reservoir for the pathogen. Understanding this concept is fundamental in infection control procedures, as breaking this chain at any point — especially by preventing infections in susceptible individuals — can halt the spread of disease.