What is the in-use test, and why is it more useful than other methods of evaluating disinfectants?

Question

What will be an ideal response?

Answer 1

The in-use test is a method of evaluating antimicrobial agents such as disinfectants or antiseptics. It involves collecting specimens from objects that need to be disinfected, both before and after the disinfecting agent is applied. Then the specimens are inoculated into growth media, and the presence or absence of growth is an indicator of the effectiveness of the agent. The in-use test is regarded as an informative and useful test because it makes use of microbes that are actually found in the area of concern, and it gives a "real-life" picture of how the antimicrobial agent will work in that situation. Conversely, other tests, such as the disk-diffusion test or the use-dilution test, are not as useful because they rely on standardized conditions in a laboratory environment, and using test microbes that may or may not have any relation to the actual microbes that need to be targeted by the antimicrobial agent. Additionally, in some environments, many microbes form biofilms that can affect the activity of an antimicrobial agent, and these biofilms are not normally present in standardized testing procedures. Therefore, although the in-use test is not as convenient or quick as the other types of tests, it is regarded as more useful.
Bloom's Taxonomy: Application
Section: Chemical Methods of Microbial Control
Learning Outcome: 9.30