Question

Which type of test is used to determine whether disinfectant solutions actively used in a clinical setting are being used correctly?

a) Disk diffusion test
b) Minimum inhibitory concentration test
c) In-use test
d) Zone of inhibition test

Answer 1

The In-Use Test is employed to verify the correct use of disinfectant solutions in a clinical setting by testing for microbial contamination.

Step-by-step explanation:

To determine whether disinfectant solutions actively used in a clinical setting are being used correctly, the In-Use Test is deployed. This test checks for microbial contamination in the disinfectant. A 1-mL sample of the used disinfectant is diluted in 9 mL of sterile broth that contains a compound neutralizing the disinfectant. About 0.2 mL of this mixture is then plated on agar and incubated. Growth of five or more colonies on the plate indicates contamination, suggesting that the disinfectant may not be effective.

In contrast, the Disk Diffusion Test and Use-Dilution Test are more commonly used to assess the effectiveness of disinfectants against specific microbes or on surfaces, respectively. Moreover, the Kirby-Bauer Disk Diffusion Test is often employed for evaluating antibiotics' susceptibility against bacteria, and Dilution Tests are used to determine the minimum inhibitory concentration (MIC) or minimum bactericidal concentration (MBC) of antimicrobial drugs.