In the chain of infection (infectious agent, reservoir, portal of exit, mode of transmission, portal of entry, susceptible host), what is the most likely outcome if any one link is effectively broken?

• A. The infectious agent becomes more virulent to compensate for the missing link.
• B. The reservoir is eliminated in all cases, permanently eradicating the pathogen.
• C. Transmission of the infectious agent is interrupted, reducing or preventing new infections.
• D. The susceptible host immediately develops active immunity without exposure.

Answer: (C)

Verified step by step guidance

1. Understand the chain of infection, which consists of six links: infectious agent, reservoir, portal of exit, mode of transmission, portal of entry, and susceptible host.
2. Recognize that the chain of infection describes the process by which an infectious disease spreads from one host to another.
3. Analyze what happens if any one link in this chain is broken or interrupted—this means the pathogen cannot continue its transmission cycle.
4. Recall that breaking any link prevents the infectious agent from moving forward to infect a new host, thereby stopping or reducing the spread of infection.
5. Conclude that the most likely outcome of breaking any link is the interruption of transmission, which reduces or prevents new infections, rather than changes in virulence, permanent eradication, or immediate immunity.