An infectious agent unlike conventional microbes
Pathogenic prions are associated with an abnormally folded, aggregated prion protein (PrPSc). They have no viral or bacterial genome. A process effective against bacteria, enveloped viruses or bacterial spores cannot therefore be assumed effective against prions. Tissue residues, surface binding and substrate characteristics must be considered before selecting a decontamination method.
Protein detection is not infectivity
An undetectable protein signal does not necessarily demonstrate absence of infectivity. Likewise, infectivity may fall without complete removal of detectable protein. The French ANSM Standard Prion Protocol distinguishes in-vitro characterization from in-vivo infectivity reduction studies. Conventional biological indicators containing bacterial spores cannot replace prion-specific evidence.
What vaporized hydrogen peroxide and ozone studies show
Hara and colleagues investigated prions attached to stainless-steel wires in 2021. In their mouse model, a combined ozone and vaporized hydrogen peroxide process reduced infectivity more strongly than either agent separately. Transmission nevertheless persisted in some treated groups. These findings are not evidence of universal prion inactivation in laboratories or equipment, and EN 17272 compliance alone does not establish a prion claim.
A defensible control strategy
Risk assessment should cover exposed materials, possible removal or replacement, approved treatment methods, personnel protection, containment and traceability. Decisions to reuse or discard equipment require competent review against applicable guidance. For prions, a sterilizing label or bactericidal result is not sufficient: evidence must address infectivity, the tested process and its intended application.