Which of the following is an example of a portal of exit?

BTSC Staff Nurse 31 July-2025

Community Health Nursing

Medium

Appeared in: BTSC Staff Nurse 31 July-2025

Explanation

The portal of exit is the specific route a pathogen takes to leave the body of its host, which is a critical step in the chain of infection.
A sneeze is a physiological action that expels respiratory droplets from the nose and mouth.
For respiratory illnesses like the flu, these droplets contain the infectious virus, making the respiratory tract the portal of exit and the sneeze the mechanism of exit.
This directly matches the definition of a portal of exit, as the pathogen is leaving the host to be transmitted.

Option A: This describes the mode of transmission (vector-borne) and the portal of entry for the person being bitten by the mosquito. While the portal of exit for malaria from an infected human is the blood, this option focuses on the transmission event, not the exit itself.
Option C: This describes the absence of a portal of exit. An open, infected, and draining wound would be a portal of exit, but 'healing without complications' implies the skin barrier is being restored and is not shedding pathogens.
Option D: Vaccination is a primary prevention measure used to create immunity in a susceptible host. It is not part of the chain of infection for an active disease; rather, it is a way to break the chain by making the host no longer susceptible.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Chain of Infection: Portal of Exit as background academic context rather than a clinical decision trigger.
Understanding portals of exit is fundamental for nurses to implement standard and transmission-based precautions effectively.
Nursing interventions like teaching respiratory etiquette (covering coughs and sneezes), performing hand hygiene after contact with bodily fluids, and managing wound drainage are all based on blocking the pathogen's portal of exit.
What if? - If the option was 'Purulent drainage from an infected surgical wound,' it would also be a correct example of a portal of exit (the skin/mucous membranes), as the pathogen is leaving the host's body through the wound exudate.

How to Approach the Question

First, identify the key concept in the question stem: 'portal of exit'. Recall its definition within the chain of infection – the way a pathogen leaves the host.
Analyze each option to see if it fits this definition.
Option A (Malaria): This describes how the disease is transmitted by a vector (mosquito). This is the 'mode of transmission' and 'portal of entry', not exit.
Option B (Sneeze): A sneeze expels droplets from the respiratory tract. This is a classic way for respiratory pathogens to leave the body. This fits the definition.
Option C (Wound healing): Healing is the process of closing a wound, which is the opposite of a pathogen exiting. An open, draining wound would be an exit, but a healing one is not.
Option D (Vaccination): This is a preventive measure to build immunity and is unrelated to how a pathogen exits an already infected person.

Concept Tested & Keywords

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