What is the chain of infection?

Prepare for the Nurse Aide I Module B – Infection Prevention Test. Leverage multiple choice questions, detailed flashcards, and comprehensive explanations. Ensure your readiness for the exam!

Multiple Choice

What is the chain of infection?

The chain of infection describes how an infection spreads from one person to another, and it unfolds in a specific sequence with six linked steps. The infectious agent must have a place to live (reservoir), a way to leave that place (portal of exit), a method to travel to someone else (transmission), a way to enter a new person (portal of entry), and a susceptible person to become the new host. If any link is blocked or removed—such as preventing the agent from leaving, stopping the transmission route, or protecting a susceptible person—the spread stops. The best answer follows this exact sequence: infectious agent, reservoir, portal of exit, transmission, portal of entry, susceptible host. This reflects the real flow from one person to the next. Other sequences mix up the order (for example, placing the reservoir after exit or altering where transmission and entry occur), which doesn’t align with how infections biologically spread from source to new host.

The chain of infection describes how an infection spreads from one person to another, and it unfolds in a specific sequence with six linked steps. The infectious agent must have a place to live (reservoir), a way to leave that place (portal of exit), a method to travel to someone else (transmission), a way to enter a new person (portal of entry), and a susceptible person to become the new host. If any link is blocked or removed—such as preventing the agent from leaving, stopping the transmission route, or protecting a susceptible person—the spread stops.

The best answer follows this exact sequence: infectious agent, reservoir, portal of exit, transmission, portal of entry, susceptible host. This reflects the real flow from one person to the next.

Other sequences mix up the order (for example, placing the reservoir after exit or altering where transmission and entry occur), which doesn’t align with how infections biologically spread from source to new host.

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