A hospital infection control team is investigating a cluster of Clostridioides difficile infections (CDI). Which disinfectant is MOST effective for environmental decontamination of C. difficile spores on ward surfaces?
- A Sodium hypochlorite (bleach) solution at ≥1000 ppm available chlorine ✓
- B 70% isopropyl alcohol hand rub
- C Quaternary ammonium compound (QUAT) solution
- D Chlorhexidine gluconate 2% solution
Correct answer: A. Sodium hypochlorite (bleach) solution at ≥1000 ppm available chlorine
Explanation
C. difficile spores are highly resistant to alcohol and most common disinfectants including QUAT and chlorhexidine. Sodium hypochlorite (bleach) at ≥1000 ppm available chlorine is the recommended sporicidal agent for environmental decontamination during CDI outbreaks. Healthcare workers must also use soap and water for hand hygiene (not alcohol rub) because mechanical removal is needed to reduce spore load on hands — alcohol does not kill C. difficile spores. Hydrogen peroxide vapour systems are also effective for terminal decontamination.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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