NHA Phlebotomy Certification Practice Exam

To complete the chain of infection, all of the following are required except a:

1. source.

2. contaminated surface.

3. mode of transmission.

4. host.

The correct answer is: contaminated surface.

The chain of infection is a concept that outlines the process by which infections spread. It consists of several components: a source (the pathogen), a mode of transmission, a susceptible host (an individual who can become infected), and sometimes a portal of entry and exit. In this context, a contaminated surface is not a required element in completing the chain of infection. While contaminated surfaces can certainly play a role in transmitting infections (acting as a vehicle for pathogens), they are not a necessary component of the chain itself. The infection can spread through direct contact, droplets, or other means without the involvement of a contaminated surface. The other elements—source, mode of transmission, and host—are fundamental to the chain of infection. These components must all be present to ensure that an infection can be established and propagated. A source is necessary to provide the pathogen, the mode of transmission is required to spread that pathogen, and a host is needed to support the infection and sustain the pathogen. Therefore, recognizing that a contaminated surface is not essential to this chain helps clarify the dynamics of infection transmission.