A microbiology laboratory uses glutaraldehyde 2% for disinfecting flexible endoscopes. This method kills vegetative bacteria, fungi, enveloped viruses, non-enveloped viruses, and mycobacteria but does NOT destroy spores within a 20-minute contact time. What level of disinfection does this represent?
- A Intermediate-level disinfection
- B Sterilization
- C High-level disinfection ✓
- D Low-level disinfection
Explanation
High-level disinfection (HLD) eliminates all microorganisms except high numbers of bacterial spores. Glutaraldehyde 2% achieves HLD in 20–45 minutes, making it suitable for heat-sensitive semi-critical instruments (flexible endoscopes, respiratory therapy equipment) that contact mucous membranes. Sterilization requires extended glutaraldehyde exposure (6–10 hours) to kill spores, making it a chemical sterilant. Intermediate-level disinfection kills mycobacteria but not all viruses. Low-level disinfection (e.g., quaternary ammonium compounds) kills most vegetative bacteria and enveloped viruses only.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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