Certified Medical Assistant (CMA AAMA)Safety and Infection ControlHard

A medical assistant is tasked with cleaning an examination room after a patient diagnosed with Clostridioides difficile (C. diff). Which type of disinfectant is most effective against C. diff spores?

  1. AQuaternary ammonium compounds
  2. BAlcohol-based hand rubs
  3. CChlorine-based solutions (e.g., bleach)
  4. DPhenolics
Show answer & explanation

Correct answer: C. Chlorine-based solutions (e.g., bleach)

Clostridioides difficile (C. diff) produces spores that are highly resistant to many common disinfectants, including alcohols, quaternary ammonium compounds, and phenolics. Chlorine-based solutions, such as bleach (sodium hypochlorite), are recommended for environmental disinfection in C. diff outbreaks because they are sporicidal.

Why the other options are wrong

  • A. Quaternary ammonium compounds are not sporicidal and ineffective against C. diff spores.
  • B. Alcohol-based hand rubs are ineffective against C. diff spores.
  • D. Phenolics are not sporicidal and generally ineffective against C. diff spores.

C. diff Disinfection

Specific disinfection protocols required to eliminate Clostridioides difficile spores from environmental surfaces.

  • C. diff produces highly resistant spores.
  • Alcohol and quats are ineffective against spores.
  • Bleach is a recommended sporicidal agent.

Memory trick: C. diff needs Bleach, not Booze!

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