Which sequence of events best describes how an infection occurs within healthcare settings?

• A. Mode of transmission → Infection → Reservoir → Susceptible host
• B. Reservoir → Mode of transmission → Susceptible host → Infection
• C. Infection → Reservoir → Susceptible host → Mode of transmission
• D. Susceptible host → Reservoir → Infection → Mode of transmission

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the key terms involved in the infection process within healthcare settings: 'Reservoir' is the source where the infectious agent normally lives and multiplies; 'Mode of transmission' is how the infectious agent is transferred from the reservoir to a new host; 'Susceptible host' is an individual who can become infected; and 'Infection' is the establishment and multiplication of the infectious agent in the host.
2. Step 2: Recognize the logical sequence of events for an infection to occur: first, the infectious agent must be present in a reservoir; then it must be transmitted via a mode of transmission; next, it must reach a susceptible host; and finally, infection occurs when the agent successfully invades and multiplies in the host.
3. Step 3: Analyze each option by matching it against the logical sequence: Reservoir → Mode of transmission → Susceptible host → Infection.
4. Step 4: Eliminate options that start with 'Infection' or 'Susceptible host' before the reservoir or mode of transmission, as infection cannot occur without the presence of the infectious agent in a reservoir and its transmission.
5. Step 5: Conclude that the correct sequence is the one that begins with the reservoir, followed by mode of transmission, then the susceptible host, and finally infection.