Which decontamination methods are among the more effective for prions?

• A. Formalin exposure
• B. UV light
• C. Autoclaving and use of sodium hydroxide or sodium hypochlorite
• D. Cold storage

Answer: (C)

Prions are exceptionally resistant because they are misfolded proteins that lack nucleic acid and survive many standard sterilants. To reliably inactivate them you need a combination approach that both denatures the protein and disrupts its abnormal structure. Using a strong chemical treatment such as sodium hydroxide or sodium hypochlorite, followed by autoclaving, provides that dual assault: the chemical denatures and breaks down the prion protein, and the subsequent autoclaving adds heat and pressure to complete the inactivation. In contrast, formalin exposure alone isn’t reliably effective against prions, UV light doesn’t penetrate well and is ineffective for prions, and cold storage does nothing to inactivate them.