Prions (proteinaceous infectious particles) causing variant Creutzfeldt-Jakob disease (vCJD) cannot be destroyed by which standard sterilisation method?

• A Autoclaving at 121°C for 15 minutes ✓
• B Exposure to 1 N NaOH for 1 hour
• C Autoclaving at 134°C for 18 minutes in a gravity-displacement cycle
• D Combination of 1 N NaOH and subsequent autoclaving at 121°C for 30 minutes

Explanation

Prions are misfolded proteins resistant to standard autoclaving at 121°C for 15 minutes. WHO guidelines for prion decontamination recommend prolonged autoclaving at 134°C for 18 minutes (pre-vacuum cycle), treatment with 1 N NaOH for 1 hour, or a combination of both methods. Standard formaldehyde, glutaraldehyde, UV irradiation, and gamma radiation are all ineffective against prions. This is a key sterilisation exception tested in NEET PG.

Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.